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sup_prod_eq_top {s : Finset ι} {J : ι → Ideal R} (h : ∀ i, i ∈ s → I ⊔ J i = ⊤) : (I ⊔ ∏ i ∈ s, J i) = ⊤ := Finset.prod_induction _ (fun J => I ⊔ J = ⊤) (fun _ _ hJ hK => (sup_mul_eq_of_coprime_left hJ).trans hK) (by simp_rw [one_eq_top, sup_top_eq]) h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
sup_prod_eq_top
null
sup_multiset_prod_eq_top {s : Multiset (Ideal R)} (h : ∀ p ∈ s, I ⊔ p = ⊤) : I ⊔ Multiset.prod s = ⊤ := Multiset.prod_induction (I ⊔ · = ⊤) s (fun _ _ hp hq ↦ (sup_mul_eq_of_coprime_left hp).trans hq) (by simp only [one_eq_top, le_top, sup_of_le_right]) h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
sup_multiset_prod_eq_top
null
sup_iInf_eq_top {s : Finset ι} {J : ι → Ideal R} (h : ∀ i, i ∈ s → I ⊔ J i = ⊤) : (I ⊔ ⨅ i ∈ s, J i) = ⊤ := by rw [eq_top_iff, ← sup_prod_eq_top h, ← Finset.inf_eq_iInf] grw [prod_le_inf]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
sup_iInf_eq_top
null
prod_sup_eq_top {s : Finset ι} {J : ι → Ideal R} (h : ∀ i, i ∈ s → J i ⊔ I = ⊤) : (∏ i ∈ s, J i) ⊔ I = ⊤ := by rw [sup_comm, sup_prod_eq_top]; intro i hi; rw [sup_comm, h i hi]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
prod_sup_eq_top
null
iInf_sup_eq_top {s : Finset ι} {J : ι → Ideal R} (h : ∀ i, i ∈ s → J i ⊔ I = ⊤) : (⨅ i ∈ s, J i) ⊔ I = ⊤ := by rw [sup_comm, sup_iInf_eq_top]; intro i hi; rw [sup_comm, h i hi]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
iInf_sup_eq_top
null
sup_pow_eq_top {n : ℕ} (h : I ⊔ J = ⊤) : I ⊔ J ^ n = ⊤ := by rw [← Finset.card_range n, ← Finset.prod_const] exact sup_prod_eq_top fun _ _ => h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
sup_pow_eq_top
null
pow_sup_eq_top {n : ℕ} (h : I ⊔ J = ⊤) : I ^ n ⊔ J = ⊤ := by rw [← Finset.card_range n, ← Finset.prod_const] exact prod_sup_eq_top fun _ _ => h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
pow_sup_eq_top
null
pow_sup_pow_eq_top {m n : ℕ} (h : I ⊔ J = ⊤) : I ^ m ⊔ J ^ n = ⊤ := sup_pow_eq_top (pow_sup_eq_top h) variable (I) in @[simp]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
pow_sup_pow_eq_top
null
mul_top : I * ⊤ = I := Ideal.mul_comm ⊤ I ▸ Submodule.top_smul I
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
mul_top
null
@[simp] multiset_prod_eq_bot {R : Type*} [CommSemiring R] [IsDomain R] {s : Multiset (Ideal R)} : s.prod = ⊥ ↔ ⊥ ∈ s := Multiset.prod_eq_zero_iff
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
multiset_prod_eq_bot
A product of ideals in an integral domain is zero if and only if one of the terms is zero.
span_pair_mul_span_pair (w x y z : R) : (span {w, x} : Ideal R) * span {y, z} = span {w * y, w * z, x * y, x * z} := by simp_rw [span_insert, sup_mul, mul_sup, span_singleton_mul_span_singleton, sup_assoc]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
span_pair_mul_span_pair
null
isCoprime_iff_codisjoint : IsCoprime I J ↔ Codisjoint I J := by rw [IsCoprime, codisjoint_iff] constructor · rintro ⟨x, y, hxy⟩ rw [eq_top_iff_one] apply (show x * I + y * J ≤ I ⊔ J from sup_le (mul_le_left.trans le_sup_left) (mul_le_left.trans le_sup_right)) rw [hxy] simp only [one_eq_top, Submodule.mem_top] · intro h refine ⟨1, 1, ?_⟩ simpa only [one_eq_top, top_mul, Submodule.add_eq_sup]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isCoprime_iff_codisjoint
null
isCoprime_of_isMaximal [I.IsMaximal] [J.IsMaximal] (ne : I ≠ J) : IsCoprime I J := by rw [isCoprime_iff_codisjoint, isMaximal_def] at * exact IsCoatom.codisjoint_of_ne ‹_› ‹_› ne
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isCoprime_of_isMaximal
null
isCoprime_iff_add : IsCoprime I J ↔ I + J = 1 := by rw [isCoprime_iff_codisjoint, codisjoint_iff, add_eq_sup, one_eq_top]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isCoprime_iff_add
null
isCoprime_iff_exists : IsCoprime I J ↔ ∃ i ∈ I, ∃ j ∈ J, i + j = 1 := by rw [← add_eq_one_iff, isCoprime_iff_add]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isCoprime_iff_exists
null
isCoprime_iff_sup_eq : IsCoprime I J ↔ I ⊔ J = ⊤ := by rw [isCoprime_iff_codisjoint, codisjoint_iff]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isCoprime_iff_sup_eq
null
coprime_of_no_prime_ge {I J : Ideal R} (h : ∀ P, I ≤ P → J ≤ P → ¬IsPrime P) : IsCoprime I J := by rw [isCoprime_iff_sup_eq] by_contra hIJ obtain ⟨P, hP, hIJ⟩ := Ideal.exists_le_maximal _ hIJ exact h P (le_trans le_sup_left hIJ) (le_trans le_sup_right hIJ) hP.isPrime open List in
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
coprime_of_no_prime_ge
null
isCoprime_tfae : TFAE [IsCoprime I J, Codisjoint I J, I + J = 1, ∃ i ∈ I, ∃ j ∈ J, i + j = 1, I ⊔ J = ⊤] := by rw [← isCoprime_iff_codisjoint, ← isCoprime_iff_add, ← isCoprime_iff_exists, ← isCoprime_iff_sup_eq] simp
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isCoprime_tfae
null
_root_.IsCoprime.codisjoint (h : IsCoprime I J) : Codisjoint I J := isCoprime_iff_codisjoint.mp h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
_root_.IsCoprime.codisjoint
null
_root_.IsCoprime.add_eq (h : IsCoprime I J) : I + J = 1 := isCoprime_iff_add.mp h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
_root_.IsCoprime.add_eq
null
_root_.IsCoprime.exists (h : IsCoprime I J) : ∃ i ∈ I, ∃ j ∈ J, i + j = 1 := isCoprime_iff_exists.mp h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
_root_.IsCoprime.exists
null
_root_.IsCoprime.sup_eq (h : IsCoprime I J) : I ⊔ J = ⊤ := isCoprime_iff_sup_eq.mp h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
_root_.IsCoprime.sup_eq
null
inf_eq_mul_of_isCoprime (coprime : IsCoprime I J) : I ⊓ J = I * J := (Ideal.mul_eq_inf_of_coprime coprime.sup_eq).symm
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
inf_eq_mul_of_isCoprime
null
isCoprime_span_singleton_iff (x y : R) : IsCoprime (span <| singleton x) (span <| singleton y) ↔ IsCoprime x y := by simp_rw [isCoprime_iff_codisjoint, codisjoint_iff, eq_top_iff_one, mem_span_singleton_sup, mem_span_singleton] constructor · rintro ⟨a, _, ⟨b, rfl⟩, e⟩; exact ⟨a, b, mul_comm b y ▸ e⟩ · rintro ⟨a, b, e⟩; exact ⟨a, _, ⟨b, rfl⟩, mul_comm y b ▸ e⟩
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isCoprime_span_singleton_iff
null
isCoprime_biInf {J : ι → Ideal R} {s : Finset ι} (hf : ∀ j ∈ s, IsCoprime I (J j)) : IsCoprime I (⨅ j ∈ s, J j) := by classical simp_rw [isCoprime_iff_add] at * induction s using Finset.induction with | empty => simp | insert i s _ hs => rw [Finset.iInf_insert, inf_comm, one_eq_top, eq_top_iff, ← one_eq_top] set K := ⨅ j ∈ s, J j calc 1 = I + K := (hs fun j hj ↦ hf j (Finset.mem_insert_of_mem hj)).symm _ = I + K*(I + J i) := by rw [hf i (Finset.mem_insert_self i s), mul_one] _ = (1+K)*I + K*J i := by ring _ ≤ I + K ⊓ J i := add_le_add mul_le_left mul_le_inf
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isCoprime_biInf
null
radical (I : Ideal R) : Ideal R where carrier := { r | ∃ n : ℕ, r ^ n ∈ I } zero_mem' := ⟨1, (pow_one (0 : R)).symm ▸ I.zero_mem⟩ add_mem' := fun {_ _} ⟨m, hxmi⟩ ⟨n, hyni⟩ => ⟨m + n - 1, add_pow_add_pred_mem_of_pow_mem I hxmi hyni⟩ smul_mem' {r s} := fun ⟨n, h⟩ ↦ ⟨n, (mul_pow r s n).symm ▸ I.mul_mem_left (r ^ n) h⟩
def
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical
The radical of an ideal `I` consists of the elements `r` such that `r ^ n ∈ I` for some `n`.
mem_radical_iff {r : R} : r ∈ I.radical ↔ ∃ n : ℕ, r ^ n ∈ I := Iff.rfl
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
mem_radical_iff
null
IsRadical (I : Ideal R) : Prop := I.radical ≤ I
def
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsRadical
An ideal is radical if it contains its radical.
le_radical : I ≤ radical I := fun r hri => ⟨1, (pow_one r).symm ▸ hri⟩
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
le_radical
null
radical_eq_iff : I.radical = I ↔ I.IsRadical := by rw [le_antisymm_iff, and_iff_left le_radical, IsRadical] alias ⟨_, IsRadical.radical⟩ := radical_eq_iff
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_eq_iff
An ideal is radical iff it is equal to its radical.
isRadical_iff_pow_one_lt (k : ℕ) (hk : 1 < k) : I.IsRadical ↔ ∀ r, r ^ k ∈ I → r ∈ I := ⟨fun h _r hr ↦ h ⟨k, hr⟩, fun h x ⟨n, hx⟩ ↦ k.pow_imp_self_of_one_lt hk _ (fun _ _ ↦ .inr ∘ I.smul_mem _) h n x hx⟩ variable (R) in
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isRadical_iff_pow_one_lt
null
radical_top : (radical ⊤ : Ideal R) = ⊤ := (eq_top_iff_one _).2 ⟨0, Submodule.mem_top⟩
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_top
null
radical_mono (H : I ≤ J) : radical I ≤ radical J := fun _ ⟨n, hrni⟩ => ⟨n, H hrni⟩ variable (I)
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_mono
null
radical_isRadical : (radical I).IsRadical := fun r ⟨n, k, hrnki⟩ => ⟨n * k, (pow_mul r n k).symm ▸ hrnki⟩ @[simp]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_isRadical
null
radical_idem : radical (radical I) = radical I := (radical_isRadical I).radical variable {I}
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_idem
null
IsRadical.radical_le_iff (hJ : J.IsRadical) : I.radical ≤ J ↔ I ≤ J := ⟨le_trans le_radical, fun h => hJ.radical ▸ radical_mono h⟩
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsRadical.radical_le_iff
null
radical_le_radical_iff : radical I ≤ radical J ↔ I ≤ radical J := (radical_isRadical J).radical_le_iff
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_le_radical_iff
null
radical_eq_top : radical I = ⊤ ↔ I = ⊤ := ⟨fun h => (eq_top_iff_one _).2 <| let ⟨n, hn⟩ := (eq_top_iff_one _).1 h @one_pow R _ n ▸ hn, fun h => h.symm ▸ radical_top R⟩
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_eq_top
null
IsPrime.isRadical (H : IsPrime I) : I.IsRadical := fun _ ⟨n, hrni⟩ => H.mem_of_pow_mem n hrni
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.isRadical
null
IsPrime.radical (H : IsPrime I) : radical I = I := IsRadical.radical H.isRadical
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.radical
null
mem_radical_of_pow_mem {I : Ideal R} {x : R} {m : ℕ} (hx : x ^ m ∈ radical I) : x ∈ radical I := radical_idem I ▸ ⟨m, hx⟩
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
mem_radical_of_pow_mem
null
disjoint_powers_iff_notMem (y : R) (hI : I.IsRadical) : Disjoint (Submonoid.powers y : Set R) ↑I ↔ y ∉ I.1 := by refine ⟨fun h => Set.disjoint_left.1 h (Submonoid.mem_powers _), fun h => disjoint_iff.mpr (eq_bot_iff.mpr ?_)⟩ rintro x ⟨⟨n, rfl⟩, hx'⟩ exact h (hI <| mem_radical_of_pow_mem <| le_radical hx') @[deprecated (since := "2025-05-23")] alias disjoint_powers_iff_not_mem := disjoint_powers_iff_notMem variable (I J)
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
disjoint_powers_iff_notMem
null
radical_sup : radical (I ⊔ J) = radical (radical I ⊔ radical J) := le_antisymm (radical_mono <| sup_le_sup le_radical le_radical) <| radical_le_radical_iff.2 <| sup_le (radical_mono le_sup_left) (radical_mono le_sup_right)
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_sup
null
radical_inf : radical (I ⊓ J) = radical I ⊓ radical J := le_antisymm (le_inf (radical_mono inf_le_left) (radical_mono inf_le_right)) fun r ⟨⟨m, hrm⟩, ⟨n, hrn⟩⟩ => ⟨m + n, (pow_add r m n).symm ▸ I.mul_mem_right _ hrm, (pow_add r m n).symm ▸ J.mul_mem_left _ hrn⟩ variable {I J} in
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_inf
null
IsRadical.inf (hI : IsRadical I) (hJ : IsRadical J) : IsRadical (I ⊓ J) := by rw [IsRadical, radical_inf]; exact inf_le_inf hI hJ
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsRadical.inf
null
isRadical_bot_iff : (⊥ : Ideal R).IsRadical ↔ IsReduced R := by simp only [IsRadical, SetLike.le_def, Ideal.mem_radical_iff, Ideal.mem_bot, forall_exists_index, isReduced_iff, IsNilpotent]
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isRadical_bot_iff
null
isRadical_bot [IsReduced R] : (⊥ : Ideal R).IsRadical := by rwa [Ideal.isRadical_bot_iff]
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isRadical_bot
null
radicalInfTopHom : InfTopHom (Ideal R) (Ideal R) where toFun := radical map_inf' := radical_inf map_top' := radical_top _ @[simp]
def
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radicalInfTopHom
`Ideal.radical` as an `InfTopHom`, bundling in that it distributes over `inf`.
radicalInfTopHom_apply (I : Ideal R) : radicalInfTopHom I = radical I := rfl open Finset in
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radicalInfTopHom_apply
null
radical_finset_inf {ι} {s : Finset ι} {f : ι → Ideal R} {i : ι} (hi : i ∈ s) (hs : ∀ ⦃y⦄, y ∈ s → (f y).radical = (f i).radical) : (s.inf f).radical = (f i).radical := by rw [← radicalInfTopHom_apply, map_finset_inf, ← Finset.inf'_eq_inf ⟨_, hi⟩] exact Finset.inf'_eq_of_forall _ _ hs
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_finset_inf
null
radical_iInf_le {ι} (I : ι → Ideal R) : radical (⨅ i, I i) ≤ ⨅ i, radical (I i) := le_iInf fun _ ↦ radical_mono (iInf_le _ _)
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_iInf_le
The reverse inclusion does not hold for e.g. `I := fun n : ℕ ↦ Ideal.span {(2 ^ n : ℤ)}`.
isRadical_iInf {ι} (I : ι → Ideal R) (hI : ∀ i, IsRadical (I i)) : IsRadical (⨅ i, I i) := (radical_iInf_le I).trans (iInf_mono hI)
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isRadical_iInf
null
radical_mul : radical (I * J) = radical I ⊓ radical J := by refine le_antisymm ?_ fun r ⟨⟨m, hrm⟩, ⟨n, hrn⟩⟩ => ⟨m + n, (pow_add r m n).symm ▸ mul_mem_mul hrm hrn⟩ have := radical_mono <| @mul_le_inf _ _ I J simp_rw [radical_inf I J] at this assumption variable {I J}
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_mul
null
IsPrime.radical_le_iff (hJ : IsPrime J) : I.radical ≤ J ↔ I ≤ J := IsRadical.radical_le_iff hJ.isRadical
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.radical_le_iff
null
radical_eq_sInf (I : Ideal R) : radical I = sInf { J : Ideal R | I ≤ J ∧ IsPrime J } := le_antisymm (le_sInf fun _ hJ ↦ hJ.2.radical_le_iff.2 hJ.1) fun r hr ↦ by_contradiction fun hri ↦ let ⟨m, hIm, hm⟩ := zorn_le_nonempty₀ { K : Ideal R | r ∉ radical K } (fun c hc hcc y hyc => ⟨sSup c, fun ⟨n, hrnc⟩ => let ⟨_, hyc, hrny⟩ := (Submodule.mem_sSup_of_directed ⟨y, hyc⟩ hcc.directedOn).1 hrnc hc hyc ⟨n, hrny⟩, fun _ => le_sSup⟩) I hri have hrm : r ∉ radical m := hm.prop have : ∀ x ∉ m, r ∈ radical (m ⊔ span {x}) := fun x hxm => by_contradiction fun hrmx => hxm <| by rw [hm.eq_of_le hrmx le_sup_left] exact Submodule.mem_sup_right <| mem_span_singleton_self x have : IsPrime m := ⟨by rintro rfl; rw [radical_top] at hrm; exact hrm trivial, fun {x y} hxym => or_iff_not_imp_left.2 fun hxm => by_contradiction fun hym => let ⟨n, hrn⟩ := this _ hxm let ⟨p, hpm, q, hq, hpqrn⟩ := Submodule.mem_sup.1 hrn let ⟨c, hcxq⟩ := mem_span_singleton'.1 hq let ⟨k, hrk⟩ := this _ hym let ⟨f, hfm, g, hg, hfgrk⟩ := Submodule.mem_sup.1 hrk let ⟨d, hdyg⟩ := mem_span_singleton'.1 hg hrm ⟨n + k, by rw [pow_add, ← hpqrn, ← hcxq, ← hfgrk, ← hdyg, add_mul, mul_add (c * x), mul_assoc c x (d * y), mul_left_comm x, ← mul_assoc] refine m.add_mem (m.mul_mem_right _ hpm) (m.add_mem (m.mul_mem_left _ hfm) (m.mul_mem_left _ hxym))⟩⟩ hrm <| this.radical.symm ▸ (sInf_le ⟨hIm, this⟩ : sInf { J : Ideal R | I ≤ J ∧ IsPrime J } ≤ m) hr
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_eq_sInf
null
isRadical_bot_of_noZeroDivisors {R} [CommSemiring R] [NoZeroDivisors R] : (⊥ : Ideal R).IsRadical := fun _ hx => hx.recOn fun _ hn => pow_eq_zero hn @[simp]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isRadical_bot_of_noZeroDivisors
null
radical_bot_of_noZeroDivisors {R : Type u} [CommSemiring R] [NoZeroDivisors R] : radical (⊥ : Ideal R) = ⊥ := eq_bot_iff.2 isRadical_bot_of_noZeroDivisors
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_bot_of_noZeroDivisors
null
top_pow (n : ℕ) : (⊤ ^ n : Ideal R) = ⊤ := Nat.recOn n one_eq_top fun n ih => by rw [pow_succ, ih, top_mul] @[simp]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
top_pow
null
pow_eq_top_iff {n : ℕ} : I ^ n = ⊤ ↔ I = ⊤ ∨ n = 0 := by refine ⟨fun h ↦ or_iff_not_imp_right.mpr fun hn ↦ (eq_top_iff_one _).mpr <| pow_le_self hn <| (eq_top_iff_one _).mp h, ?_⟩ rintro (h | h) · rw [h, top_pow] · rw [h, pow_zero, one_eq_top]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
pow_eq_top_iff
null
natCast_eq_top {n : ℕ} (hn : n ≠ 0) : (n : Ideal R) = ⊤ := natCast_eq_one hn |>.trans one_eq_top
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
natCast_eq_top
null
ofNat_eq_top {n : ℕ} [n.AtLeastTwo] : (ofNat(n) : Ideal R) = ⊤ := ofNat_eq_one.trans one_eq_top variable (I)
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
ofNat_eq_top
`3 : Ideal R` is *not* the ideal generated by 3 (which would be spelt `Ideal.span {3}`), it is simply `1 + 1 + 1 = ⊤`.
radical_pow : ∀ {n}, n ≠ 0 → radical (I ^ n) = radical I | 1, _ => by simp | n + 2, _ => by rw [pow_succ, radical_mul, radical_pow n.succ_ne_zero, inf_idem]
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
radical_pow
null
IsPrime.mul_le {I J P : Ideal R} (hp : IsPrime P) : I * J ≤ P ↔ I ≤ P ∨ J ≤ P := by rw [or_comm, Ideal.mul_le] simp_rw [hp.mul_mem_iff_mem_or_mem, SetLike.le_def, ← forall_or_left, or_comm, forall_or_left]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.mul_le
null
IsPrime.inf_le {I J P : Ideal R} (hp : IsPrime P) : I ⊓ J ≤ P ↔ I ≤ P ∨ J ≤ P := ⟨fun h ↦ hp.mul_le.1 <| mul_le_inf.trans h, fun h ↦ h.elim inf_le_left.trans inf_le_right.trans⟩
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.inf_le
null
IsPrime.multiset_prod_le {s : Multiset (Ideal R)} {P : Ideal R} (hp : IsPrime P) : s.prod ≤ P ↔ ∃ I ∈ s, I ≤ P := s.induction_on (by simp [hp.ne_top]) fun I s ih ↦ by simp [hp.mul_le, ih]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.multiset_prod_le
null
IsPrime.multiset_prod_map_le {s : Multiset ι} (f : ι → Ideal R) {P : Ideal R} (hp : IsPrime P) : (s.map f).prod ≤ P ↔ ∃ i ∈ s, f i ≤ P := by simp_rw [hp.multiset_prod_le, Multiset.mem_map, exists_exists_and_eq_and]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.multiset_prod_map_le
null
IsPrime.multiset_prod_mem_iff_exists_mem {I : Ideal R} (hI : I.IsPrime) (s : Multiset R) : s.prod ∈ I ↔ ∃ p ∈ s, p ∈ I := by simpa [span_singleton_le_iff_mem] using (hI.multiset_prod_map_le (span {·}))
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.multiset_prod_mem_iff_exists_mem
null
IsPrime.pow_le_iff {I P : Ideal R} [hP : P.IsPrime] {n : ℕ} (hn : n ≠ 0) : I ^ n ≤ P ↔ I ≤ P := by have h : (Multiset.replicate n I).prod ≤ P ↔ _ := hP.multiset_prod_le simp_rw [Multiset.prod_replicate, Multiset.mem_replicate, ne_eq, hn, not_false_eq_true, true_and, exists_eq_left] at h exact h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.pow_le_iff
null
IsPrime.le_of_pow_le {I P : Ideal R} [hP : P.IsPrime] {n : ℕ} (h : I ^ n ≤ P) : I ≤ P := by by_cases hn : n = 0 · rw [hn, pow_zero, one_eq_top] at h exact fun ⦃_⦄ _ ↦ h Submodule.mem_top · exact (pow_le_iff hn).mp h
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.le_of_pow_le
null
IsPrime.prod_le {s : Finset ι} {f : ι → Ideal R} {P : Ideal R} (hp : IsPrime P) : s.prod f ≤ P ↔ ∃ i ∈ s, f i ≤ P := hp.multiset_prod_map_le f
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.prod_le
null
IsPrime.prod_mem_iff {s : Finset ι} {x : ι → R} {p : Ideal R} [hp : p.IsPrime] : ∏ i ∈ s, x i ∈ p ↔ ∃ i ∈ s, x i ∈ p := by simp_rw [← span_singleton_le_iff_mem, ← prod_span_singleton] exact hp.prod_le
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.prod_mem_iff
The product of a finite number of elements in the commutative semiring `R` lies in the prime ideal `p` if and only if at least one of those elements is in `p`.
IsPrime.prod_mem_iff_exists_mem {I : Ideal R} (hI : I.IsPrime) (s : Finset R) : s.prod (fun x ↦ x) ∈ I ↔ ∃ p ∈ s, p ∈ I := by rw [Finset.prod_eq_multiset_prod, Multiset.map_id'] exact hI.multiset_prod_mem_iff_exists_mem s.val
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.prod_mem_iff_exists_mem
null
IsPrime.inf_le' {s : Finset ι} {f : ι → Ideal R} {P : Ideal R} (hp : IsPrime P) : s.inf f ≤ P ↔ ∃ i ∈ s, f i ≤ P := ⟨fun h ↦ hp.prod_le.1 <| prod_le_inf.trans h, fun ⟨_, his, hip⟩ ↦ (Finset.inf_le his).trans hip⟩
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
IsPrime.inf_le'
null
subset_union {R : Type u} [Ring R] {I J K : Ideal R} : (I : Set R) ⊆ J ∪ K ↔ I ≤ J ∨ I ≤ K := AddSubgroupClass.subset_union
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
subset_union
null
subset_union_prime' {R : Type u} [CommRing R] {s : Finset ι} {f : ι → Ideal R} {a b : ι} (hp : ∀ i ∈ s, IsPrime (f i)) {I : Ideal R} : ((I : Set R) ⊆ f a ∪ f b ∪ ⋃ i ∈ (↑s : Set ι), f i) ↔ I ≤ f a ∨ I ≤ f b ∨ ∃ i ∈ s, I ≤ f i := by suffices ((I : Set R) ⊆ f a ∪ f b ∪ ⋃ i ∈ (↑s : Set ι), f i) → I ≤ f a ∨ I ≤ f b ∨ ∃ i ∈ s, I ≤ f i from ⟨this, fun h => Or.casesOn h (fun h => Set.Subset.trans h <| Set.Subset.trans Set.subset_union_left Set.subset_union_left) fun h => Or.casesOn h (fun h => Set.Subset.trans h <| Set.Subset.trans Set.subset_union_right Set.subset_union_left) fun ⟨i, his, hi⟩ => by refine Set.Subset.trans hi <| Set.Subset.trans ?_ Set.subset_union_right exact Set.subset_biUnion_of_mem (u := fun x ↦ (f x : Set R)) (Finset.mem_coe.2 his)⟩ generalize hn : s.card = n; intro h induction n generalizing a b s with | zero => clear hp rw [Finset.card_eq_zero] at hn subst hn rw [Finset.coe_empty, Set.biUnion_empty, Set.union_empty, subset_union] at h simpa only [exists_prop, Finset.notMem_empty, false_and, exists_false, or_false] | succ n ih => classical replace hn : ∃ (i : ι) (t : Finset ι), i ∉ t ∧ insert i t = s ∧ t.card = n := Finset.card_eq_succ.1 hn rcases hn with ⟨i, t, hit, rfl, hn⟩ replace hp : IsPrime (f i) ∧ ∀ x ∈ t, IsPrime (f x) := (t.forall_mem_insert _ _).1 hp by_cases Ht : ∃ j ∈ t, f j ≤ f i · obtain ⟨j, hjt, hfji⟩ : ∃ j ∈ t, f j ≤ f i := Ht obtain ⟨u, hju, rfl⟩ : ∃ u, j ∉ u ∧ insert j u = t := ⟨t.erase j, t.notMem_erase j, Finset.insert_erase hjt⟩ have hp' : ∀ k ∈ insert i u, IsPrime (f k) := by rw [Finset.forall_mem_insert] at hp ⊢ exact ⟨hp.1, hp.2.2⟩ have hiu : i ∉ u := mt Finset.mem_insert_of_mem hit have hn' : (insert i u).card = n := by rwa [Finset.card_insert_of_notMem] at hn ⊢ exacts [hiu, hju] have h' : (I : Set R) ⊆ f a ∪ f b ∪ ⋃ k ∈ (↑(insert i u) : Set ι), f k := by rw [Finset.coe_insert] at h ⊢ rw [Finset.coe_insert] at h simp only [Set.biUnion_insert] at h ⊢ rw [← Set.union_assoc (f i : Set R), Set.union_eq_self_of_subset_right hfji] at h exact h specialize ih hp' hn' h' ...
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
subset_union_prime'
null
@[stacks 00DS] subset_union_prime {R : Type u} [CommRing R] {s : Finset ι} {f : ι → Ideal R} (a b : ι) (hp : ∀ i ∈ s, i ≠ a → i ≠ b → IsPrime (f i)) {I : Ideal R} : ((I : Set R) ⊆ ⋃ i ∈ (↑s : Set ι), f i) ↔ ∃ i ∈ s, I ≤ f i := suffices ((I : Set R) ⊆ ⋃ i ∈ (↑s : Set ι), f i) → ∃ i, i ∈ s ∧ I ≤ f i by have aux := fun h => (bex_def.2 <| this h) simp_rw [exists_prop] at aux refine ⟨aux, fun ⟨i, his, hi⟩ ↦ Set.Subset.trans hi ?_⟩ apply Set.subset_biUnion_of_mem (show i ∈ (↑s : Set ι) from his) fun h : (I : Set R) ⊆ ⋃ i ∈ (↑s : Set ι), f i => by classical by_cases has : a ∈ s · obtain ⟨t, hat, rfl⟩ : ∃ t, a ∉ t ∧ insert a t = s := ⟨s.erase a, Finset.notMem_erase a s, Finset.insert_erase has⟩ by_cases hbt : b ∈ t · obtain ⟨u, hbu, rfl⟩ : ∃ u, b ∉ u ∧ insert b u = t := ⟨t.erase b, Finset.notMem_erase b t, Finset.insert_erase hbt⟩ have hp' : ∀ i ∈ u, IsPrime (f i) := by intro i hiu refine hp i (Finset.mem_insert_of_mem (Finset.mem_insert_of_mem hiu)) ?_ ?_ <;> rintro rfl <;> solve_by_elim only [Finset.mem_insert_of_mem, *] rw [Finset.coe_insert, Finset.coe_insert, Set.biUnion_insert, Set.biUnion_insert, ← Set.union_assoc, subset_union_prime' hp'] at h rwa [Finset.exists_mem_insert, Finset.exists_mem_insert] · have hp' : ∀ j ∈ t, IsPrime (f j) := by intro j hj refine hp j (Finset.mem_insert_of_mem hj) ?_ ?_ <;> rintro rfl <;> solve_by_elim only [Finset.mem_insert_of_mem, *] rw [Finset.coe_insert, Set.biUnion_insert, ← Set.union_self (f a : Set R), subset_union_prime' hp', ← or_assoc, or_self_iff] at h rwa [Finset.exists_mem_insert] · by_cases hbs : b ∈ s · obtain ⟨t, hbt, rfl⟩ : ∃ t, b ∉ t ∧ insert b t = s := ⟨s.erase b, Finset.notMem_erase b s, Finset.insert_erase hbs⟩ have hp' : ∀ j ∈ t, IsPrime (f j) := by intro j hj refine hp j (Finset.mem_insert_of_mem hj) ?_ ?_ <;> rintro rfl <;> solve_by_elim only [Finset.mem_insert_of_mem, *] rw [Finset.coe_insert, Set.biUnion_insert, ← Set.union_self (f b : Set R), subset_union_prime' hp', ← or_assoc, or_self_iff] at h rwa [Finset.exists_mem_insert] rcases s.eq_empty_or_nonempty with hse | hsne · subst hse rw [Finset.coe_empty, Set.biUnion_empty, Set.subset_empty_iff] at h have : (I : Set R) ≠ ∅ := Set.Nonempty.ne_empty (Set.nonempty_of_mem I.zero_mem) exact absurd h this · obtain ⟨i, his⟩ := hsne obtain ⟨t, _, rfl⟩ : ∃ t, i ∉ t ∧ insert i t = s := ⟨s.erase i, Finset.notMem_erase i s, Finset.insert_erase his⟩ have hp' : ∀ j ∈ t, IsPrime (f j) := by ...
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
subset_union_prime
Prime avoidance. Atiyah-Macdonald 1.11, Eisenbud 3.3, Matsumura Ex.1.6.
subset_union_prime_finite {R ι : Type*} [CommRing R] {s : Set ι} (hs : s.Finite) {f : ι → Ideal R} (a b : ι) (hp : ∀ i ∈ s, i ≠ a → i ≠ b → (f i).IsPrime) {I : Ideal R} : ((I : Set R) ⊆ ⋃ i ∈ s, f i) ↔ ∃ i ∈ s, I ≤ f i := by rcases Set.Finite.exists_finset hs with ⟨t, ht⟩ have heq : ⋃ i ∈ s, f i = ⋃ i ∈ t, (f i : Set R) := by ext simpa using exists_congr (fun i ↦ (and_congr_left fun a ↦ ht i).symm) have hmem_union : ((I : Set R) ⊆ ⋃ i ∈ s, f i) ↔ ((I : Set R) ⊆ ⋃ i ∈ (t : Set ι), f i) := (congrArg _ heq).to_iff rw [hmem_union, Ideal.subset_union_prime a b (fun i hin ↦ hp i ((ht i).mp hin))] exact exists_congr (fun i ↦ and_congr_left fun _ ↦ ht i)
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
subset_union_prime_finite
Another version of prime avoidance using `Set.Finite` instead of `Finset`.
le_of_dvd {I J : Ideal R} : I ∣ J → J ≤ I | ⟨_, h⟩ => h.symm ▸ le_trans mul_le_inf inf_le_left @[simp]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
le_of_dvd
If `I` divides `J`, then `I` contains `J`. In a Dedekind domain, to divide and contain are equivalent, see `Ideal.dvd_iff_le`.
dvd_bot {I : Ideal R} : I ∣ ⊥ := dvd_zero I
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
dvd_bot
null
@[simp high] isUnit_iff {I : Ideal R} : IsUnit I ↔ I = ⊤ := isUnit_iff_dvd_one.trans ((@one_eq_top R _).symm ▸ ⟨fun h => eq_top_iff.mpr (Ideal.le_of_dvd h), fun h => ⟨⊤, by rw [mul_top, h]⟩⟩)
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
isUnit_iff
See also `isUnit_iff_eq_one`.
uniqueUnits : Unique (Ideal R)ˣ where default := 1 uniq u := Units.ext (show (u : Ideal R) = 1 by rw [isUnit_iff.mp u.isUnit, one_eq_top])
instance
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
uniqueUnits
null
noncomputable finsuppTotal : (ι →₀ I) →ₗ[R] M := (Finsupp.linearCombination R v).comp (Finsupp.mapRange.linearMap I.subtype) variable {ι M v}
def
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
finsuppTotal
A variant of `Finsupp.linearCombination` that takes in vectors valued in `I`.
finsuppTotal_apply (f : ι →₀ I) : finsuppTotal ι M I v f = f.sum fun i x => (x : R) • v i := by dsimp [finsuppTotal] rw [Finsupp.linearCombination_apply, Finsupp.sum_mapRange_index] exact fun _ => zero_smul _ _
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
finsuppTotal_apply
null
finsuppTotal_apply_eq_of_fintype [Fintype ι] (f : ι →₀ I) : finsuppTotal ι M I v f = ∑ i, (f i : R) • v i := by rw [finsuppTotal_apply, Finsupp.sum_fintype] exact fun _ => zero_smul _ _
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
finsuppTotal_apply_eq_of_fintype
null
range_finsuppTotal : LinearMap.range (finsuppTotal ι M I v) = I • Submodule.span R (Set.range v) := by ext rw [Submodule.mem_ideal_smul_span_iff_exists_sum] refine ⟨fun ⟨f, h⟩ => ⟨Finsupp.mapRange.linearMap I.subtype f, fun i => (f i).2, h⟩, ?_⟩ rintro ⟨a, ha, rfl⟩ classical refine ⟨a.mapRange (fun r => if h : r ∈ I then ⟨r, h⟩ else 0) (by simp only [Submodule.zero_mem, ↓reduceDIte]; rfl), ?_⟩ rw [finsuppTotal_apply, Finsupp.sum_mapRange_index] · apply Finsupp.sum_congr intro i _ rw [dif_pos (ha i)] · exact fun _ => zero_smul _ _
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
range_finsuppTotal
null
Finsupp.mem_ideal_span_range_iff_exists_finsupp {x : R} {v : α → R} : x ∈ Ideal.span (Set.range v) ↔ ∃ c : α →₀ R, (c.sum fun i a => a * v i) = x := Finsupp.mem_span_range_iff_exists_finsupp
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
Finsupp.mem_ideal_span_range_iff_exists_finsupp
null
Ideal.mem_span_range_iff_exists_fun [Fintype α] {x : R} {v : α → R} : x ∈ Ideal.span (Set.range v) ↔ ∃ c : α → R, ∑ i, c i * v i = x := Submodule.mem_span_range_iff_exists_fun _ @[deprecated (since := "2025-04-02")] alias mem_ideal_span_range_iff_exists_fun := Ideal.mem_span_range_iff_exists_fun
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
Ideal.mem_span_range_iff_exists_fun
An element `x` lies in the span of `v` iff it can be written as sum `∑ cᵢ • vᵢ = x`.
Associates.mk_ne_zero' {R : Type*} [CommSemiring R] {r : R} : Associates.mk (Ideal.span {r} : Ideal R) ≠ 0 ↔ r ≠ 0 := by rw [Associates.mk_ne_zero, Ideal.zero_eq_bot, Ne, Ideal.span_singleton_eq_bot] open scoped nonZeroDivisors in
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
Associates.mk_ne_zero'
null
Ideal.span_singleton_nonZeroDivisors {R : Type*} [CommSemiring R] [NoZeroDivisors R] {r : R} : span {r} ∈ (Ideal R)⁰ ↔ r ∈ R⁰ := by cases subsingleton_or_nontrivial R · simp_rw [← nonZeroDivisorsRight_eq_nonZeroDivisors] exact ⟨fun _ _ _ ↦ Subsingleton.eq_zero _, fun _ _ _ ↦ Subsingleton.eq_zero _⟩ · rw [mem_nonZeroDivisors_iff_ne_zero, mem_nonZeroDivisors_iff_ne_zero, ne_eq, zero_eq_bot, span_singleton_eq_bot]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
Ideal.span_singleton_nonZeroDivisors
null
Ideal.primeCompl_le_nonZeroDivisors {R : Type*} [CommSemiring R] [NoZeroDivisors R] (P : Ideal R) [P.IsPrime] : P.primeCompl ≤ nonZeroDivisors R := le_nonZeroDivisors_of_noZeroDivisors <| not_not_intro P.zero_mem
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
Ideal.primeCompl_le_nonZeroDivisors
null
moduleSubmodule : Module (Ideal R) (Submodule R M) where smul_add := smul_sup add_smul := sup_smul mul_smul := Submodule.mul_smul one_smul := by simp zero_smul := bot_smul smul_zero := smul_bot
instance
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
moduleSubmodule
null
span_smul_eq (s : Set R) (N : Submodule R M) : Ideal.span s • N = s • N := by rw [← coe_set_smul, coe_span_smul] @[simp]
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
span_smul_eq
null
set_smul_top_eq_span (s : Set R) : s • ⊤ = Ideal.span s := (span_smul_eq s ⊤).symm.trans (Ideal.span s).mul_top
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
set_smul_top_eq_span
null
smul_le_span (s : Set R) (I : Ideal R) : s • I ≤ Ideal.span s := by simp [← Submodule.set_smul_top_eq_span, smul_le_smul_left] variable {A B} [Semiring A] [Semiring B] [Algebra R A] [Algebra R B] open Submodule
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
smul_le_span
null
algebraIdeal : Algebra (Ideal R) (Submodule R A) where __ := moduleSubmodule algebraMap := { toFun := map (Algebra.linearMap R A) map_one' := by rw [one_eq_span, map_span, Set.image_singleton, Algebra.linearMap_apply, map_one, one_eq_span] map_mul' := (Submodule.map_mul · · <| Algebra.ofId R A) map_zero' := map_bot _ map_add' := (map_sup · · _) } commutes' I M := mul_comm_of_commute <| by rintro _ ⟨r, _, rfl⟩ a _; apply Algebra.commutes smul_def' I M := le_antisymm (smul_le.mpr fun r hr a ha ↦ by rw [Algebra.smul_def]; exact Submodule.mul_mem_mul ⟨r, hr, rfl⟩ ha) (Submodule.mul_le.mpr <| by rintro _ ⟨r, hr, rfl⟩ a ha; rw [Algebra.linearMap_apply, ← Algebra.smul_def] exact Submodule.smul_mem_smul hr ha)
instance
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
algebraIdeal
null
@[simps!] mapAlgHom (f : A →ₐ[R] B) : Submodule R A →ₐ[Ideal R] Submodule R B where __ := mapHom f commutes' I := (map_comp _ _ I).symm.trans (congr_arg (map · I) <| LinearMap.ext f.commutes)
def
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
mapAlgHom
`Submonoid.map` as an `AlgHom`, when applied to an `AlgHom`.
@[simps!] mapAlgEquiv (f : A ≃ₐ[R] B) : Submodule R A ≃ₐ[Ideal R] Submodule R B where __ := mapAlgHom f invFun := mapAlgHom f.symm left_inv I := (map_comp _ _ I).symm.trans <| (congr_arg (map · I) <| LinearMap.ext (f.left_inv ·)).trans (map_id I) right_inv I := (map_comp _ _ I).symm.trans <| (congr_arg (map · I) <| LinearMap.ext (f.right_inv ·)).trans (map_id I)
def
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
mapAlgEquiv
null
Ideal.exists_subset_radical_span_sup_of_subset_radical_sup {R : Type*} [CommSemiring R] (s : Set R) (I J : Ideal R) (hs : s ⊆ (I ⊔ J).radical) : ∃ (t : s → R), Set.range t ⊆ I ∧ s ⊆ (span (Set.range t) ⊔ J).radical := by replace hs : ∀ z : s, ∃ (m : ℕ) (a b : R) (ha : a ∈ I) (hb : b ∈ J), a + b = z ^ m := by rintro ⟨z, hzs⟩ simp only [Ideal.radical, Submodule.mem_sup] at hs obtain ⟨m, y, hyq, b, hb, hy⟩ := hs hzs exact ⟨m, y, b, hyq, hb, hy⟩ choose m a b ha hb heq using hs refine ⟨a, by rwa [Set.range_subset_iff], fun z hz ↦ ⟨m ⟨z, hz⟩, heq ⟨z, hz⟩ ▸ ?_⟩⟩ exact Ideal.add_mem _ (mem_sup_left (subset_span ⟨⟨z, hz⟩, rfl⟩)) (mem_sup_right <| hb _) @[deprecated (since := "2025-05-13")] alias Ideal.exists_subset_radical_span_sup_span_of_subset_radical_sup := Ideal.exists_subset_radical_span_sup_of_subset_radical_sup
lemma
RingTheory
[ "Mathlib.Algebra.Algebra.Operations", "Mathlib.Algebra.Module.BigOperators", "Mathlib.Data.Fintype.Lattice", "Mathlib.RingTheory.Coprime.Lemmas", "Mathlib.RingTheory.Ideal.Basic", "Mathlib.RingTheory.Nilpotent.Defs", "Mathlib.RingTheory.NonUnitalSubsemiring.Basic" ]
Mathlib/RingTheory/Ideal/Operations.lean
Ideal.exists_subset_radical_span_sup_of_subset_radical_sup
null
comap_eq_of_scalar_tower_quotient [Algebra R S] [Algebra (R ⧸ p) (S ⧸ P)] [IsScalarTower R (R ⧸ p) (S ⧸ P)] (h : Function.Injective (algebraMap (R ⧸ p) (S ⧸ P))) : comap (algebraMap R S) P = p := by ext x rw [mem_comap, ← Quotient.eq_zero_iff_mem, ← Quotient.eq_zero_iff_mem, Quotient.mk_algebraMap, IsScalarTower.algebraMap_apply R (R ⧸ p) (S ⧸ P), Quotient.algebraMap_eq] constructor · intro hx exact (injective_iff_map_eq_zero (algebraMap (R ⧸ p) (S ⧸ P))).mp h _ hx · intro hx rw [hx, RingHom.map_zero] variable [Algebra R S]
theorem
RingTheory
[ "Mathlib.Algebra.Algebra.Tower", "Mathlib.Algebra.Group.Subgroup.Actions", "Mathlib.RingTheory.Ideal.Pointwise", "Mathlib.RingTheory.Ideal.Quotient.Operations" ]
Mathlib/RingTheory/Ideal/Over.lean
comap_eq_of_scalar_tower_quotient
If there is an injective map `R/p → S/P` such that following diagram commutes: ``` R → S ↓ ↓ R/p → S/P ``` then `P` lies over `p`.
Quotient.algebraQuotientMapQuotient : Algebra (R ⧸ p) (S ⧸ map (algebraMap R S) p) := Ideal.Quotient.algebraQuotientOfLEComap le_comap_map @[simp]
instance
RingTheory
[ "Mathlib.Algebra.Algebra.Tower", "Mathlib.Algebra.Group.Subgroup.Actions", "Mathlib.RingTheory.Ideal.Pointwise", "Mathlib.RingTheory.Ideal.Quotient.Operations" ]
Mathlib/RingTheory/Ideal/Over.lean
Quotient.algebraQuotientMapQuotient
`R / p` has a canonical map to `S / pS`.