statement
stringlengths
1
2.88k
proof
stringlengths
0
13.9k
type
stringclasses
10 values
symbolic_name
stringlengths
1
131
library
stringclasses
417 values
filename
stringlengths
17
80
imports
listlengths
0
16
deps
listlengths
0
64
docstring
stringlengths
0
10.2k
source_url
stringclasses
1 value
commit
stringclasses
1 value
num_mul_denom_eq_num_iff_eq' {x y : K} : y * algebra_map A K (denom A x) = algebra_map A K (num A x) ↔ x = y
⟨λ h, by simpa only [eq_comm, mk'_num_denom] using eq_mk'_iff_mul_eq.mpr h, λ h, eq_mk'_iff_mul_eq.mp (by rw [h, mk'_num_denom])⟩
lemma
is_fraction_ring.num_mul_denom_eq_num_iff_eq'
ring_theory.localization
src/ring_theory/localization/num_denom.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.integer", "ring_theory.unique_factorization_domain" ]
[ "algebra_map", "num" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
num_mul_denom_eq_num_mul_denom_iff_eq {x y : K} : num A y * denom A x = num A x * denom A y ↔ x = y
⟨λ h, by simpa only [mk'_num_denom] using mk'_eq_of_eq' h, λ h, by rw h⟩
lemma
is_fraction_ring.num_mul_denom_eq_num_mul_denom_iff_eq
ring_theory.localization
src/ring_theory/localization/num_denom.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.integer", "ring_theory.unique_factorization_domain" ]
[ "num" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
eq_zero_of_num_eq_zero {x : K} (h : num A x = 0) : x = 0
num_mul_denom_eq_num_iff_eq'.mp (by rw [zero_mul, h, ring_hom.map_zero])
lemma
is_fraction_ring.eq_zero_of_num_eq_zero
ring_theory.localization
src/ring_theory/localization/num_denom.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.integer", "ring_theory.unique_factorization_domain" ]
[ "num", "ring_hom.map_zero", "zero_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_integer_of_is_unit_denom {x : K} (h : is_unit (denom A x : A)) : is_integer A x
begin cases h with d hd, have d_ne_zero : algebra_map A K (denom A x) ≠ 0 := is_fraction_ring.to_map_ne_zero_of_mem_non_zero_divisors (denom A x).2, use ↑d⁻¹ * num A x, refine trans _ (mk'_num_denom A x), rw [map_mul, map_units_inv, hd], apply mul_left_cancel₀ d_ne_zero, rw [←mul_assoc, mul_inv_cancel...
lemma
is_fraction_ring.is_integer_of_is_unit_denom
ring_theory.localization
src/ring_theory/localization/num_denom.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.integer", "ring_theory.unique_factorization_domain" ]
[ "algebra_map", "is_fraction_ring.to_map_ne_zero_of_mem_non_zero_divisors", "is_unit", "map_mul", "map_units_inv", "mul_inv_cancel", "mul_left_cancel₀", "num", "one_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_unit_denom_of_num_eq_zero {x : K} (h : num A x = 0) : is_unit (denom A x : A)
num_denom_reduced A x (h.symm ▸ dvd_zero _) dvd_rfl
lemma
is_fraction_ring.is_unit_denom_of_num_eq_zero
ring_theory.localization
src/ring_theory/localization/num_denom.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.integer", "ring_theory.unique_factorization_domain" ]
[ "dvd_rfl", "dvd_zero", "is_unit", "num" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule (I : ideal R) : submodule R S
submodule.map (algebra.linear_map R S) I
def
is_localization.coe_submodule
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "algebra.linear_map", "ideal", "submodule", "submodule.map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_coe_submodule (I : ideal R) {x : S} : x ∈ coe_submodule S I ↔ ∃ y : R, y ∈ I ∧ algebra_map R S y = x
iff.rfl
lemma
is_localization.mem_coe_submodule
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "algebra_map", "ideal" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_mono {I J : ideal R} (h : I ≤ J) : coe_submodule S I ≤ coe_submodule S J
submodule.map_mono h
lemma
is_localization.coe_submodule_mono
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "submodule.map_mono" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_bot : coe_submodule S (⊥ : ideal R) = ⊥
by rw [coe_submodule, submodule.map_bot]
lemma
is_localization.coe_submodule_bot
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "submodule.map_bot" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_top : coe_submodule S (⊤ : ideal R) = 1
by rw [coe_submodule, submodule.map_top, submodule.one_eq_range]
lemma
is_localization.coe_submodule_top
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "submodule.map_top", "submodule.one_eq_range" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_sup (I J : ideal R) : coe_submodule S (I ⊔ J) = coe_submodule S I ⊔ coe_submodule S J
submodule.map_sup _ _ _
lemma
is_localization.coe_submodule_sup
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "submodule.map_sup" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_mul (I J : ideal R) : coe_submodule S (I * J) = coe_submodule S I * coe_submodule S J
submodule.map_mul _ _ (algebra.of_id R S)
lemma
is_localization.coe_submodule_mul
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "algebra.of_id", "ideal", "submodule.map_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_fg (hS : function.injective (algebra_map R S)) (I : ideal R) : submodule.fg (coe_submodule S I) ↔ submodule.fg I
⟨submodule.fg_of_fg_map _ (linear_map.ker_eq_bot.mpr hS), submodule.fg.map _⟩
lemma
is_localization.coe_submodule_fg
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "algebra_map", "ideal", "submodule.fg", "submodule.fg.map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_span (s : set R) : coe_submodule S (ideal.span s) = submodule.span R ((algebra_map R S) '' s)
by { rw [is_localization.coe_submodule, ideal.span, submodule.map_span], refl }
lemma
is_localization.coe_submodule_span
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "algebra_map", "ideal.span", "is_localization.coe_submodule", "submodule.map_span", "submodule.span" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_span_singleton (x : R) : coe_submodule S (ideal.span {x}) = submodule.span R {(algebra_map R S) x}
by rw [coe_submodule_span, set.image_singleton]
lemma
is_localization.coe_submodule_span_singleton
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "algebra_map", "ideal.span", "set.image_singleton", "submodule.span" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_noetherian_ring (h : is_noetherian_ring R) : is_noetherian_ring S
begin rw [is_noetherian_ring_iff, is_noetherian_iff_well_founded] at h ⊢, exact order_embedding.well_founded ((is_localization.order_embedding M S).dual) h end
lemma
is_localization.is_noetherian_ring
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "is_localization.order_embedding", "is_noetherian_iff_well_founded", "is_noetherian_ring", "is_noetherian_ring_iff", "order_embedding.well_founded" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_le_coe_submodule (h : M ≤ non_zero_divisors R) {I J : ideal R} : coe_submodule S I ≤ coe_submodule S J ↔ I ≤ J
submodule.map_le_map_iff_of_injective (is_localization.injective _ h) _ _
lemma
is_localization.coe_submodule_le_coe_submodule
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "is_localization.injective", "non_zero_divisors", "submodule.map_le_map_iff_of_injective" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_strict_mono (h : M ≤ non_zero_divisors R) : strict_mono (coe_submodule S : ideal R → submodule R S)
strict_mono_of_le_iff_le (λ _ _, (coe_submodule_le_coe_submodule h).symm)
lemma
is_localization.coe_submodule_strict_mono
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "non_zero_divisors", "strict_mono", "strict_mono_of_le_iff_le", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_injective (h : M ≤ non_zero_divisors R) : function.injective (coe_submodule S : ideal R → submodule R S)
injective_of_le_imp_le _ (λ _ _, (coe_submodule_le_coe_submodule h).mp)
lemma
is_localization.coe_submodule_injective
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "injective_of_le_imp_le", "non_zero_divisors", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_is_principal {I : ideal R} (h : M ≤ non_zero_divisors R) : (coe_submodule S I).is_principal ↔ I.is_principal
begin split; unfreezingI { rintros ⟨⟨x, hx⟩⟩ }, { have x_mem : x ∈ coe_submodule S I := hx.symm ▸ submodule.mem_span_singleton_self x, obtain ⟨x, x_mem, rfl⟩ := (mem_coe_submodule _ _).mp x_mem, refine ⟨⟨x, coe_submodule_injective S h _⟩⟩, rw [ideal.submodule_span_eq, hx, coe_submodule_span_singleton] }...
lemma
is_localization.coe_submodule_is_principal
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "ideal.submodule_span_eq", "non_zero_divisors", "submodule.mem_span_singleton_self" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_span_iff {N : Type*} [add_comm_group N] [module R N] [module S N] [is_scalar_tower R S N] {x : N} {a : set N} : x ∈ submodule.span S a ↔ ∃ (y ∈ submodule.span R a) (z : M), x = mk' S 1 z • y
begin split, intro h, { refine submodule.span_induction h _ _ _ _, { rintros x hx, exact ⟨x, submodule.subset_span hx, 1, by rw [mk'_one, _root_.map_one, one_smul]⟩ }, { exact ⟨0, submodule.zero_mem _, 1, by rw [mk'_one, _root_.map_one, one_smul]⟩ }, { rintros _ _ ⟨y, hy, z, rfl⟩ ⟨y', hy', z', rfl...
lemma
is_localization.mem_span_iff
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "add_comm_group", "is_scalar_tower", "is_scalar_tower.algebra_map_smul", "mk'", "mk'_one", "mk'_surjective", "module", "mul_assoc", "mul_comm", "mul_one", "mul_right_comm", "one_mul", "one_smul", "smul_add", "smul_smul", "submodule.add_mem", "submodule.smul_mem", "submodule.span", ...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_span_map {x : S} {a : set R} : x ∈ ideal.span (algebra_map R S '' a) ↔ ∃ (y ∈ ideal.span a) (z : M), x = mk' S y z
begin refine (mem_span_iff M).trans _, split, { rw ← coe_submodule_span, rintros ⟨_, ⟨y, hy, rfl⟩, z, hz⟩, refine ⟨y, hy, z, _⟩, rw [hz, algebra.linear_map_apply, smul_eq_mul, mul_comm, mul_mk'_eq_mk'_of_mul, mul_one] }, { rintros ⟨y, hy, z, hz⟩, refine ⟨algebra_map R S y, submodule.map_mem_span...
lemma
is_localization.mem_span_map
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "algebra.linear_map_apply", "algebra_map", "ideal.span", "mk'", "mul_comm", "mul_one", "smul_eq_mul", "submodule.map_mem_span_algebra_map_image" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_le_coe_submodule {I J : ideal R} : coe_submodule K I ≤ coe_submodule K J ↔ I ≤ J
is_localization.coe_submodule_le_coe_submodule le_rfl
lemma
is_fraction_ring.coe_submodule_le_coe_submodule
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "is_localization.coe_submodule_le_coe_submodule", "le_rfl" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_strict_mono : strict_mono (coe_submodule K : ideal R → submodule R K)
strict_mono_of_le_iff_le (λ _ _, coe_submodule_le_coe_submodule.symm)
lemma
is_fraction_ring.coe_submodule_strict_mono
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "strict_mono", "strict_mono_of_le_iff_le", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_injective : function.injective (coe_submodule K : ideal R → submodule R K)
injective_of_le_imp_le _ (λ _ _, (coe_submodule_le_coe_submodule).mp)
lemma
is_fraction_ring.coe_submodule_injective
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "injective_of_le_imp_le", "submodule" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_submodule_is_principal {I : ideal R} : (coe_submodule K I).is_principal ↔ I.is_principal
is_localization.coe_submodule_is_principal _ le_rfl
lemma
is_fraction_ring.coe_submodule_is_principal
ring_theory.localization
src/ring_theory/localization/submodule.lean
[ "ring_theory.localization.fraction_ring", "ring_theory.localization.ideal", "ring_theory.principal_ideal_domain" ]
[ "ideal", "is_localization.coe_submodule_is_principal", "le_rfl" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
localization.away_equiv_adjoin (r : R) : away r ≃ₐ[R] adjoin_root (C r * X - 1)
alg_equiv.of_alg_hom { commutes' := is_localization.away.away_map.lift_eq r (is_unit_of_mul_eq_one _ _ $ root_is_inv r), .. away_lift _ r _ } (lift_hom _ (is_localization.away.inv_self r) $ by simp only [map_sub, map_mul, aeval_C, aeval_X, is_localization.away.mul_inv_self, aeval_one, sub_self]) (subsin...
def
localization.away_equiv_adjoin
ring_theory.localization.away
src/ring_theory/localization/away/adjoin_root.lean
[ "ring_theory.adjoin_root", "ring_theory.localization.away.basic" ]
[ "adjoin_root", "alg_equiv.of_alg_hom", "is_localization.away.away_map.lift_eq", "is_localization.away.inv_self", "is_localization.away.mul_inv_self", "is_unit_of_mul_eq_one", "map_mul" ]
The `R`-`alg_equiv` between the localization of `R` away from `r` and `R` with an inverse of `r` adjoined.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_localization.adjoin_inv (r : R) : is_localization.away r (adjoin_root $ C r * X - 1)
is_localization.is_localization_of_alg_equiv _ (localization.away_equiv_adjoin r)
lemma
is_localization.adjoin_inv
ring_theory.localization.away
src/ring_theory/localization/away/adjoin_root.lean
[ "ring_theory.adjoin_root", "ring_theory.localization.away.basic" ]
[ "adjoin_root", "is_localization.away", "is_localization.is_localization_of_alg_equiv", "localization.away_equiv_adjoin" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_localization.away.finite_presentation (r : R) {S} [comm_ring S] [algebra R S] [is_localization.away r S] : algebra.finite_presentation R S
(adjoin_root.finite_presentation _).equiv $ (localization.away_equiv_adjoin r).symm.trans $ is_localization.alg_equiv (submonoid.powers r) _ _
lemma
is_localization.away.finite_presentation
ring_theory.localization.away
src/ring_theory/localization/away/adjoin_root.lean
[ "ring_theory.adjoin_root", "ring_theory.localization.away.basic" ]
[ "adjoin_root.finite_presentation", "algebra", "algebra.finite_presentation", "comm_ring", "equiv", "is_localization.alg_equiv", "is_localization.away", "localization.away_equiv_adjoin", "submonoid.powers" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
away (S : Type*) [comm_semiring S] [algebra R S]
is_localization (submonoid.powers x) S
abbreviation
is_localization.away
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra", "comm_semiring", "is_localization", "submonoid.powers" ]
Given `x : R`, the typeclass `is_localization.away x S` states that `S` is isomorphic to the localization of `R` at the submonoid generated by `x`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
inv_self : S
mk' S (1 : R) ⟨x, submonoid.mem_powers _⟩
def
is_localization.away.inv_self
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "mk'", "submonoid.mem_powers" ]
Given `x : R` and a localization map `F : R →+* S` away from `x`, `inv_self` is `(F x)⁻¹`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_inv_self : algebra_map R S x * inv_self x = 1
by { convert is_localization.mk'_mul_mk'_eq_one _ 1, symmetry, apply is_localization.mk'_one }
lemma
is_localization.away.mul_inv_self
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra_map", "is_localization.mk'_mul_mk'_eq_one", "is_localization.mk'_one", "mul_inv_self" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
lift (hg : is_unit (g x)) : S →+* P
is_localization.lift $ λ (y : submonoid.powers x), show is_unit (g y.1), begin obtain ⟨n, hn⟩ := y.2, rw [←hn, g.map_pow], exact is_unit.map (pow_monoid_hom n : P →* P) hg, end
def
is_localization.away.lift
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.lift", "is_unit", "is_unit.map", "lift", "pow_monoid_hom", "submonoid.powers" ]
Given `x : R`, a localization map `F : R →+* S` away from `x`, and a map of `comm_semiring`s `g : R →+* P` such that `g x` is invertible, the homomorphism induced from `S` to `P` sending `z : S` to `g y * (g x)⁻ⁿ`, where `y : R, n : ℕ` are such that `z = F y * (F x)⁻ⁿ`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
away_map.lift_eq (hg : is_unit (g x)) (a : R) : lift x hg ((algebra_map R S) a) = g a
lift_eq _ _
lemma
is_localization.away.away_map.lift_eq
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra_map", "is_unit", "lift" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
away_map.lift_comp (hg : is_unit (g x)) : (lift x hg).comp (algebra_map R S) = g
lift_comp _
lemma
is_localization.away.away_map.lift_comp
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra_map", "is_unit", "lift", "lift_comp" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
away_to_away_right (y : R) [algebra R P] [is_localization.away (x * y) P] : S →+* P
lift x $ show is_unit ((algebra_map R P) x), from is_unit_of_mul_eq_one ((algebra_map R P) x) (mk' P y ⟨x * y, submonoid.mem_powers _⟩) $ by rw [mul_mk'_eq_mk'_of_mul, mk'_self]
def
is_localization.away.away_to_away_right
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra", "algebra_map", "is_localization.away", "is_unit", "is_unit_of_mul_eq_one", "lift", "mk'", "submonoid.mem_powers" ]
Given `x y : R` and localizations `S`, `P` away from `x` and `x * y` respectively, the homomorphism induced from `S` to `P`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map (f : R →+* P) (r : R) [is_localization.away r S] [is_localization.away (f r) Q] : S →+* Q
is_localization.map Q f (show submonoid.powers r ≤ (submonoid.powers (f r)).comap f, by { rintros x ⟨n, rfl⟩, use n, simp })
def
is_localization.away.map
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.away", "is_localization.map", "submonoid.powers" ]
Given a map `f : R →+* S` and an element `r : R`, we may construct a map `Rᵣ →+* Sᵣ`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
at_units (H : ∀ x : M, is_unit (x : R)) : R ≃ₐ[R] S
begin refine alg_equiv.of_bijective (algebra.of_id R S) ⟨_, _⟩, { intros x y hxy, obtain ⟨c, eq⟩ := (is_localization.eq_iff_exists M S).mp hxy, obtain ⟨u, hu⟩ := H c, rwa [← hu, units.mul_right_inj] at eq }, { intros y, obtain ⟨⟨x, s⟩, eq⟩ := is_localization.surj M y, obtain ⟨u, hu⟩ := H s, ...
def
is_localization.at_units
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "alg_equiv.of_bijective", "alg_hom.coe_mk", "algebra.of_id", "is_unit", "mul_assoc", "ring_hom.map_mul", "ring_hom.to_fun_eq_coe", "units.mul_right_inj" ]
The localization at a module of units is isomorphic to the ring
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
at_unit (x : R) (e : is_unit x) [is_localization.away x S] : R ≃ₐ[R] S
begin apply at_units R (submonoid.powers x), rintros ⟨xn, n, hxn⟩, obtain ⟨u, hu⟩ := e, rw is_unit_iff_exists_inv, use u.inv ^ n, simp[← hxn, ← hu, ← mul_pow] end
def
is_localization.at_unit
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.away", "is_unit", "is_unit_iff_exists_inv", "mul_pow", "submonoid.powers" ]
The localization away from a unit is isomorphic to the ring
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
at_one [is_localization.away (1 : R) S] : R ≃ₐ[R] S
@at_unit R _ S _ _ (1 : R) is_unit_one _
def
is_localization.at_one
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.away", "is_unit_one" ]
The localization at one is isomorphic to the ring.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
away_of_is_unit_of_bijective {R : Type*} (S : Type*) [comm_ring R] [comm_ring S] [algebra R S] {r : R} (hr : is_unit r) (H : function.bijective (algebra_map R S)) : is_localization.away r S
{ map_units := by { rintros ⟨_, n, rfl⟩, exact (algebra_map R S).is_unit_map (hr.pow _) }, surj := λ z, by { obtain ⟨z', rfl⟩ := H.2 z, exact ⟨⟨z', 1⟩, by simp⟩ }, eq_iff_exists := λ x y, begin erw H.1.eq_iff, split, { rintro rfl, exact ⟨1, rfl⟩ }, { rintro ⟨⟨_, n, rfl⟩, e⟩, exact (hr.pow _).mul_rig...
lemma
is_localization.away_of_is_unit_of_bijective
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra", "algebra_map", "comm_ring", "is_localization.away", "is_unit" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
away_lift (f : R →+* P) (r : R) (hr : is_unit (f r)) : localization.away r →+* P
is_localization.away.lift r hr
abbreviation
localization.away_lift
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.away.lift", "is_unit", "localization.away" ]
Given a map `f : R →+* S` and an element `r : R`, such that `f r` is invertible, we may construct a map `Rᵣ →+* S`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
away_map (f : R →+* P) (r : R) : localization.away r →+* localization.away (f r)
is_localization.away.map _ _ f r
abbreviation
localization.away_map
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.away.map", "localization.away" ]
Given a map `f : R →+* S` and an element `r : R`, we may construct a map `Rᵣ →+* Sᵣ`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow (m : ℤ) : B
if hm : 0 ≤ m then algebra_map _ _ x ^ m.nat_abs else mk' _ (1 : R) (submonoid.pow x m.nat_abs)
def
self_zpow
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra_map", "mk'", "submonoid.pow" ]
`self_zpow x (m : ℤ)` is `x ^ m` as an element of the localization away from `x`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_of_nonneg {n : ℤ} (hn : 0 ≤ n) : self_zpow x B n = algebra_map R B x ^ n.nat_abs
dif_pos hn
lemma
self_zpow_of_nonneg
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra_map", "self_zpow" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_coe_nat (d : ℕ) : self_zpow x B d = (algebra_map R B x)^d
self_zpow_of_nonneg _ _ (int.coe_nat_nonneg d)
lemma
self_zpow_coe_nat
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra_map", "int.coe_nat_nonneg", "self_zpow", "self_zpow_of_nonneg" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_zero : self_zpow x B 0 = 1
by simp [self_zpow_of_nonneg _ _ le_rfl]
lemma
self_zpow_zero
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "le_rfl", "self_zpow", "self_zpow_of_nonneg" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_of_neg {n : ℤ} (hn : n < 0) : self_zpow x B n = mk' _ (1 : R) (submonoid.pow x n.nat_abs)
dif_neg hn.not_le
lemma
self_zpow_of_neg
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "mk'", "self_zpow", "submonoid.pow" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_of_nonpos {n : ℤ} (hn : n ≤ 0) : self_zpow x B n = mk' _ (1 : R) (submonoid.pow x n.nat_abs)
begin by_cases hn0 : n = 0, { simp [hn0, self_zpow_zero, submonoid.pow_apply] }, { simp [self_zpow_of_neg _ _ (lt_of_le_of_ne hn hn0)] } end
lemma
self_zpow_of_nonpos
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "mk'", "self_zpow", "self_zpow_of_neg", "self_zpow_zero", "submonoid.pow", "submonoid.pow_apply" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_neg_coe_nat (d : ℕ) : self_zpow x B (-d) = mk' _ (1 : R) (submonoid.pow x d)
by simp [self_zpow_of_nonpos _ _ (neg_nonpos.mpr (int.coe_nat_nonneg d))]
lemma
self_zpow_neg_coe_nat
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "int.coe_nat_nonneg", "mk'", "self_zpow", "self_zpow_of_nonpos", "submonoid.pow" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_sub_cast_nat {n m : ℕ} : self_zpow x B (n - m) = mk' _ (x ^ n) (submonoid.pow x m)
begin by_cases h : m ≤ n, { rw [is_localization.eq_mk'_iff_mul_eq, submonoid.pow_apply, subtype.coe_mk, ← int.coe_nat_sub h, self_zpow_coe_nat, ← map_pow, ← map_mul, ← pow_add, nat.sub_add_cancel h] }, { rw [← neg_sub, ← int.coe_nat_sub (le_of_not_le h), self_zpow_neg_coe_nat, is_localizat...
lemma
self_zpow_sub_cast_nat
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.eq_mk'_iff_mul_eq", "is_localization.mk'_eq_iff_eq", "map_mul", "map_pow", "mk'", "pow_add", "self_zpow", "self_zpow_coe_nat", "self_zpow_neg_coe_nat", "submonoid.pow", "submonoid.pow_apply", "subtype.coe_mk" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_add {n m : ℤ} : self_zpow x B (n + m) = self_zpow x B n * self_zpow x B m
begin cases le_or_lt 0 n with hn hn; cases le_or_lt 0 m with hm hm, { rw [self_zpow_of_nonneg _ _ hn, self_zpow_of_nonneg _ _ hm, self_zpow_of_nonneg _ _ (add_nonneg hn hm), int.nat_abs_add_nonneg hn hm, pow_add] }, { have : n + m = n.nat_abs - m.nat_abs, { rw [int.nat_abs_of_nonneg hn, int.of_nat_nat...
lemma
self_zpow_add
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.mk'_eq_mul_mk'_one", "map_pow", "mul_comm", "one_mul", "pow_add", "self_zpow", "self_zpow_of_neg", "self_zpow_of_nonneg", "self_zpow_sub_cast_nat" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_mul_neg (d : ℤ) : self_zpow x B d * self_zpow x B (-d) = 1
begin by_cases hd : d ≤ 0, { erw [self_zpow_of_nonpos x B hd, self_zpow_of_nonneg, ← map_pow, int.nat_abs_neg, is_localization.mk'_spec, map_one], apply nonneg_of_neg_nonpos, rwa [neg_neg]}, { erw [self_zpow_of_nonneg x B (le_of_not_le hd), self_zpow_of_nonpos, ← map_pow, int.nat_abs_neg, @is_l...
lemma
self_zpow_mul_neg
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "is_localization.mk'_spec", "is_localization.mk'_spec'", "map_one", "map_pow", "self_zpow", "self_zpow_of_nonneg", "self_zpow_of_nonpos", "submonoid.pow", "submonoid.powers" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_neg_mul (d : ℤ) : self_zpow x B (-d) * self_zpow x B d = 1
by rw [mul_comm, self_zpow_mul_neg x B d]
lemma
self_zpow_neg_mul
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "mul_comm", "self_zpow", "self_zpow_mul_neg" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_zpow_pow_sub (a : R) (b : B) (m d : ℤ) : (self_zpow x B (m - d)) * mk' B a (1 : submonoid.powers x) = b ↔ (self_zpow x B m) * mk' B a (1 : submonoid.powers x) = (self_zpow x B d) * b
begin rw [sub_eq_add_neg, self_zpow_add, mul_assoc, mul_comm _ (mk' B a 1), ← mul_assoc], split, { intro h, have := congr_arg (λ s : B, s * self_zpow x B d) h, simp only at this, rwa [mul_assoc, mul_assoc, self_zpow_neg_mul, mul_one, mul_comm b _] at this}, { intro h, have := congr_arg (λ s : B,...
lemma
self_zpow_pow_sub
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "mk'", "mul_assoc", "mul_comm", "mul_one", "self_zpow", "self_zpow_add", "self_zpow_mul_neg", "self_zpow_neg_mul", "submonoid.powers" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exists_reduced_fraction' {b : B} (hb : b ≠ 0) (hx : irreducible x) : ∃ (a : R) (n : ℤ), ¬ x ∣ a ∧ self_zpow x B n * algebra_map R B a = b
begin classical, obtain ⟨⟨a₀, y⟩, H⟩ := surj (submonoid.powers x) b, obtain ⟨d, hy⟩ := (submonoid.mem_powers_iff y.1 x).mp y.2, have ha₀ : a₀ ≠ 0, { haveI := @is_domain_of_le_non_zero_divisors B _ R _ _ _ (submonoid.powers x) _ (powers_le_non_zero_divisors_of_no_zero_divisors hx.ne_zero), simp only ...
theorem
exists_reduced_fraction'
ring_theory.localization.away
src/ring_theory/localization/away/basic.lean
[ "ring_theory.unique_factorization_domain", "ring_theory.localization.basic" ]
[ "algebra_map", "irreducible", "is_localization.injective", "is_localization.mk'_one", "is_localization.to_map_ne_zero_of_mem_non_zero_divisors", "map_mul", "map_pow", "mk'_one", "mul_comm", "mul_ne_zero", "pow_ne_zero", "powers_le_non_zero_divisors_of_no_zero_divisors", "self_zpow", "self_...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_range_eq_map {R S : Type*} [comm_ring R] [comm_ring S] (p : mv_polynomial σ R) (f : R →+* S) : finsupp.map_range f f.map_zero p = map f p
begin -- `finsupp.map_range_finset_sum` expects `f : R →+ S` change finsupp.map_range (f : R →+ S) (f : R →+ S).map_zero p = map f p, rw [p.as_sum, finsupp.map_range_finset_sum, (map f).map_sum], refine finset.sum_congr rfl (assume n _, _), rw [map_monomial, ← single_eq_monomial, finsupp.map_range_single, sin...
lemma
mv_polynomial.map_range_eq_map
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "comm_ring", "finsupp.map_range", "finsupp.map_range_finset_sum", "finsupp.map_range_single", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
restrict_total_degree : submodule R (mv_polynomial σ R)
finsupp.supported _ _ {n | n.sum (λn e, e) ≤ m }
def
mv_polynomial.restrict_total_degree
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "finsupp.supported", "mv_polynomial", "submodule" ]
The submodule of polynomials of total degree less than or equal to `m`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
restrict_degree (m : ℕ) : submodule R (mv_polynomial σ R)
finsupp.supported _ _ {n | ∀i, n i ≤ m }
def
mv_polynomial.restrict_degree
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "finsupp.supported", "mv_polynomial", "submodule" ]
The submodule of polynomials such that the degree with respect to each individual variable is less than or equal to `m`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_restrict_total_degree (p : mv_polynomial σ R) : p ∈ restrict_total_degree σ R m ↔ p.total_degree ≤ m
begin rw [total_degree, finset.sup_le_iff], refl end
lemma
mv_polynomial.mem_restrict_total_degree
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "finset.sup_le_iff", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_restrict_degree (p : mv_polynomial σ R) (n : ℕ) : p ∈ restrict_degree σ R n ↔ (∀s ∈ p.support, ∀i, (s : σ →₀ ℕ) i ≤ n)
begin rw [restrict_degree, finsupp.mem_supported], refl end
lemma
mv_polynomial.mem_restrict_degree
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "finsupp.mem_supported", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_restrict_degree_iff_sup [decidable_eq σ] (p : mv_polynomial σ R) (n : ℕ) : p ∈ restrict_degree σ R n ↔ ∀i, p.degrees.count i ≤ n
begin simp only [mem_restrict_degree, degrees_def, multiset.count_finset_sup, finsupp.count_to_multiset, finset.sup_le_iff], exact ⟨assume h n s hs, h s hs n, assume h s hs n, h n s hs⟩ end
lemma
mv_polynomial.mem_restrict_degree_iff_sup
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "finset.sup_le_iff", "finsupp.count_to_multiset", "multiset.count_finset_sup", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
basis_monomials : basis (σ →₀ ℕ) R (mv_polynomial σ R)
finsupp.basis_single_one
def
mv_polynomial.basis_monomials
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "basis", "finsupp.basis_single_one", "mv_polynomial" ]
The monomials form a basis on `mv_polynomial σ R`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_basis_monomials : (basis_monomials σ R : (σ →₀ ℕ) → mv_polynomial σ R) = λ s, monomial s 1
rfl
lemma
mv_polynomial.coe_basis_monomials
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
linear_independent_X : linear_independent R (X : σ → mv_polynomial σ R)
(basis_monomials σ R).linear_independent.comp (λ s : σ, finsupp.single s 1) (finsupp.single_left_injective one_ne_zero)
lemma
mv_polynomial.linear_independent_X
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "finsupp.single", "finsupp.single_left_injective", "linear_independent", "linear_independent.comp", "mv_polynomial", "one_ne_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
basis_monomials : basis ℕ R R[X]
basis.of_repr (to_finsupp_iso_alg R).to_linear_equiv
def
polynomial.basis_monomials
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[ "basis" ]
The monomials form a basis on `R[X]`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_basis_monomials : (basis_monomials R : ℕ → R[X]) = λ s, monomial s 1
_root_.funext $ λ n, of_finsupp_single _ _
lemma
polynomial.coe_basis_monomials
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/basic.lean
[ "algebra.char_p.basic", "data.polynomial.algebra_map", "data.mv_polynomial.variables", "linear_algebra.finsupp_vector_space" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_homogeneous [comm_semiring R] (φ : mv_polynomial σ R) (n : ℕ)
∀ ⦃d⦄, coeff d φ ≠ 0 → ∑ i in d.support, d i = n
def
mv_polynomial.is_homogeneous
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "comm_semiring", "mv_polynomial" ]
A multivariate polynomial `φ` is homogeneous of degree `n` if all monomials occuring in `φ` have degree `n`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_submodule [comm_semiring R] (n : ℕ) : submodule R (mv_polynomial σ R)
{ carrier := { x | x.is_homogeneous n }, smul_mem' := λ r a ha c hc, begin rw coeff_smul at hc, apply ha, intro h, apply hc, rw h, exact smul_zero r, end, zero_mem' := λ d hd, false.elim (hd $ coeff_zero _), add_mem' := λ a b ha hb c hc, begin rw coeff_add at hc, obtain h|h : coe...
def
mv_polynomial.homogeneous_submodule
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "comm_semiring", "mv_polynomial", "smul_zero", "submodule" ]
The submodule of homogeneous `mv_polynomial`s of degree `n`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_homogeneous_submodule [comm_semiring R] (n : ℕ) (p : mv_polynomial σ R) : p ∈ homogeneous_submodule σ R n ↔ p.is_homogeneous n
iff.rfl
lemma
mv_polynomial.mem_homogeneous_submodule
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "comm_semiring", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_submodule_eq_finsupp_supported [comm_semiring R] (n : ℕ) : homogeneous_submodule σ R n = finsupp.supported _ R {d | ∑ i in d.support, d i = n}
begin ext, rw [finsupp.mem_supported, set.subset_def], simp only [finsupp.mem_support_iff, finset.mem_coe], refl, end
lemma
mv_polynomial.homogeneous_submodule_eq_finsupp_supported
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "comm_semiring", "finset.mem_coe", "finsupp.mem_support_iff", "finsupp.mem_supported", "finsupp.supported", "set.subset_def" ]
While equal, the former has a convenient definitional reduction.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_submodule_mul [comm_semiring R] (m n : ℕ) : homogeneous_submodule σ R m * homogeneous_submodule σ R n ≤ homogeneous_submodule σ R (m + n)
begin rw submodule.mul_le, intros φ hφ ψ hψ c hc, rw [coeff_mul] at hc, obtain ⟨⟨d, e⟩, hde, H⟩ := finset.exists_ne_zero_of_sum_ne_zero hc, have aux : coeff d φ ≠ 0 ∧ coeff e ψ ≠ 0, { contrapose! H, by_cases h : coeff d φ = 0; simp only [*, ne.def, not_false_iff, zero_mul, mul_zero] at * }, specia...
lemma
mv_polynomial.homogeneous_submodule_mul
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "aux", "comm_semiring", "finset.subset_union_left", "finset.subset_union_right", "finsupp.mem_antidiagonal", "finsupp.support_add", "mul_zero", "submodule.mul_le", "zero_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_homogeneous_monomial (d : σ →₀ ℕ) (r : R) (n : ℕ) (hn : ∑ i in d.support, d i = n) : is_homogeneous (monomial d r) n
begin intros c hc, classical, rw coeff_monomial at hc, split_ifs at hc with h, { subst c, exact hn }, { contradiction } end
lemma
mv_polynomial.is_homogeneous_monomial
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_homogeneous_of_total_degree_zero {p : mv_polynomial σ R} (hp : p.total_degree = 0) : is_homogeneous p 0
begin erw [total_degree, finset.sup_eq_bot_iff] at hp, -- we have to do this in two steps to stop simp changing bot to zero simp_rw [mem_support_iff] at hp, exact hp, end
lemma
mv_polynomial.is_homogeneous_of_total_degree_zero
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finset.sup_eq_bot_iff", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_homogeneous_C (r : R) : is_homogeneous (C r : mv_polynomial σ R) 0
begin apply is_homogeneous_monomial, simp only [finsupp.zero_apply, finset.sum_const_zero], end
lemma
mv_polynomial.is_homogeneous_C
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finsupp.zero_apply", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_homogeneous_zero (n : ℕ) : is_homogeneous (0 : mv_polynomial σ R) n
(homogeneous_submodule σ R n).zero_mem
lemma
mv_polynomial.is_homogeneous_zero
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_homogeneous_one : is_homogeneous (1 : mv_polynomial σ R) 0
is_homogeneous_C _ _
lemma
mv_polynomial.is_homogeneous_one
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_homogeneous_X (i : σ) : is_homogeneous (X i : mv_polynomial σ R) 1
begin apply is_homogeneous_monomial, simp only [finsupp.support_single_ne_zero _ one_ne_zero, finset.sum_singleton], exact finsupp.single_eq_same end
lemma
mv_polynomial.is_homogeneous_X
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finsupp.single_eq_same", "finsupp.support_single_ne_zero", "mv_polynomial", "one_ne_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coeff_eq_zero (hφ : is_homogeneous φ n) (d : σ →₀ ℕ) (hd : ∑ i in d.support, d i ≠ n) : coeff d φ = 0
by { have aux := mt (@hφ d) hd, classical, rwa not_not at aux }
lemma
mv_polynomial.is_homogeneous.coeff_eq_zero
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "aux", "not_not" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
inj_right (hm : is_homogeneous φ m) (hn : is_homogeneous φ n) (hφ : φ ≠ 0) : m = n
begin obtain ⟨d, hd⟩ : ∃ d, coeff d φ ≠ 0 := exists_coeff_ne_zero hφ, rw [← hm hd, ← hn hd] end
lemma
mv_polynomial.is_homogeneous.inj_right
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
add (hφ : is_homogeneous φ n) (hψ : is_homogeneous ψ n) : is_homogeneous (φ + ψ) n
(homogeneous_submodule σ R n).add_mem hφ hψ
lemma
mv_polynomial.is_homogeneous.add
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum {ι : Type*} (s : finset ι) (φ : ι → mv_polynomial σ R) (n : ℕ) (h : ∀ i ∈ s, is_homogeneous (φ i) n) : is_homogeneous (∑ i in s, φ i) n
(homogeneous_submodule σ R n).sum_mem h
lemma
mv_polynomial.is_homogeneous.sum
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finset", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul (hφ : is_homogeneous φ m) (hψ : is_homogeneous ψ n) : is_homogeneous (φ * ψ) (m + n)
homogeneous_submodule_mul m n $ submodule.mul_mem_mul hφ hψ
lemma
mv_polynomial.is_homogeneous.mul
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "submodule.mul_mem_mul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prod {ι : Type*} (s : finset ι) (φ : ι → mv_polynomial σ R) (n : ι → ℕ) (h : ∀ i ∈ s, is_homogeneous (φ i) (n i)) : is_homogeneous (∏ i in s, φ i) (∑ i in s, n i)
begin classical, revert h, apply finset.induction_on s, { intro, simp only [is_homogeneous_one, finset.sum_empty, finset.prod_empty] }, { intros i s his IH h, simp only [his, finset.prod_insert, finset.sum_insert, not_false_iff], apply (h i (finset.mem_insert_self _ _)).mul (IH _), intros j hjs, ...
lemma
mv_polynomial.is_homogeneous.prod
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finset", "finset.induction_on", "finset.mem_insert_of_mem", "finset.mem_insert_self", "finset.prod_empty", "finset.prod_insert", "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
total_degree (hφ : is_homogeneous φ n) (h : φ ≠ 0) : total_degree φ = n
begin rw total_degree, apply le_antisymm, { apply finset.sup_le, intros d hd, rw mem_support_iff at hd, rw [finsupp.sum, hφ hd], }, { obtain ⟨d, hd⟩ : ∃ d, coeff d φ ≠ 0 := exists_coeff_ne_zero h, simp only [← hφ hd, finsupp.sum], replace hd := finsupp.mem_support_iff.mpr hd, exact finse...
lemma
mv_polynomial.is_homogeneous.total_degree
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finset.le_sup" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_submodule.gcomm_semiring : set_like.graded_monoid (homogeneous_submodule σ R)
{ one_mem := is_homogeneous_one σ R, mul_mem := λ i j xi xj, is_homogeneous.mul}
instance
mv_polynomial.is_homogeneous.homogeneous_submodule.gcomm_semiring
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "set_like.graded_monoid" ]
The homogeneous submodules form a graded ring. This instance is used by `direct_sum.comm_semiring` and `direct_sum.algebra`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_component [comm_semiring R] (n : ℕ) : mv_polynomial σ R →ₗ[R] mv_polynomial σ R
(submodule.subtype _).comp $ finsupp.restrict_dom _ _ {d | ∑ i in d.support, d i = n}
def
mv_polynomial.homogeneous_component
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "comm_semiring", "finsupp.restrict_dom", "mv_polynomial", "submodule.subtype" ]
`homogeneous_component n φ` is the part of `φ` that is homogeneous of degree `n`. See `sum_homogeneous_component` for the statement that `φ` is equal to the sum of all its homogeneous components.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coeff_homogeneous_component (d : σ →₀ ℕ) : coeff d (homogeneous_component n φ) = if ∑ i in d.support, d i = n then coeff d φ else 0
by convert finsupp.filter_apply (λ d : σ →₀ ℕ, ∑ i in d.support, d i = n) φ d
lemma
mv_polynomial.coeff_homogeneous_component
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finsupp.filter_apply" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_component_apply : homogeneous_component n φ = ∑ d in φ.support.filter (λ d, ∑ i in d.support, d i = n), monomial d (coeff d φ)
by convert finsupp.filter_eq_sum (λ d : σ →₀ ℕ, ∑ i in d.support, d i = n) φ
lemma
mv_polynomial.homogeneous_component_apply
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finsupp.filter_eq_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_component_is_homogeneous : (homogeneous_component n φ).is_homogeneous n
begin intros d hd, contrapose! hd, rw [coeff_homogeneous_component, if_neg hd] end
lemma
mv_polynomial.homogeneous_component_is_homogeneous
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_component_zero : homogeneous_component 0 φ = C (coeff 0 φ)
begin ext1 d, rcases em (d = 0) with (rfl|hd), { classical, simp only [coeff_homogeneous_component, sum_eq_zero_iff, finsupp.zero_apply, if_true, coeff_C, eq_self_iff_true, forall_true_iff] }, { rw [coeff_homogeneous_component, if_neg, coeff_C, if_neg (ne.symm hd)], simp only [finsupp.ext_iff, fin...
lemma
mv_polynomial.homogeneous_component_zero
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "em", "finsupp.ext_iff", "finsupp.zero_apply", "forall_true_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_component_C_mul (n : ℕ) (r : R) : homogeneous_component n (C r * φ) = C r * homogeneous_component n φ
by simp only [C_mul', linear_map.map_smul]
lemma
mv_polynomial.homogeneous_component_C_mul
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "linear_map.map_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_component_eq_zero' (h : ∀ d : σ →₀ ℕ, d ∈ φ.support → ∑ i in d.support, d i ≠ n) : homogeneous_component n φ = 0
begin rw [homogeneous_component_apply, sum_eq_zero], intros d hd, rw mem_filter at hd, exfalso, exact h _ hd.1 hd.2 end
lemma
mv_polynomial.homogeneous_component_eq_zero'
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_component_eq_zero (h : φ.total_degree < n) : homogeneous_component n φ = 0
begin apply homogeneous_component_eq_zero', rw [total_degree, finset.sup_lt_iff] at h, { intros d hd, exact ne_of_lt (h d hd), }, { exact lt_of_le_of_lt (nat.zero_le _) h, } end
lemma
mv_polynomial.homogeneous_component_eq_zero
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "finset.sup_lt_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum_homogeneous_component : ∑ i in range (φ.total_degree + 1), homogeneous_component i φ = φ
begin ext1 d, suffices : φ.total_degree < d.support.sum d → 0 = coeff d φ, by simpa [coeff_sum, coeff_homogeneous_component], exact λ h, (coeff_eq_zero_of_total_degree_lt h).symm end
lemma
mv_polynomial.sum_homogeneous_component
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homogeneous_component_homogeneous_polynomial (m n : ℕ) (p : mv_polynomial σ R) (h : p ∈ homogeneous_submodule σ R n) : homogeneous_component m p = if m = n then p else 0
begin simp only [mem_homogeneous_submodule] at h, ext x, rw coeff_homogeneous_component, by_cases zero_coeff : coeff x p = 0, { split_ifs, all_goals { simp only [zero_coeff, coeff_zero], }, }, { rw h zero_coeff, simp only [show n = m ↔ m = n, from eq_comm], split_ifs with h1, { refl }, {...
lemma
mv_polynomial.homogeneous_component_homogeneous_polynomial
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/homogeneous.lean
[ "algebra.direct_sum.internal", "algebra.graded_monoid", "data.mv_polynomial.variables" ]
[ "mv_polynomial" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_ideal_span_monomial_image {x : mv_polynomial σ R} {s : set (σ →₀ ℕ)} : x ∈ ideal.span ((λ s, monomial s (1 : R)) '' s) ↔ ∀ xi ∈ x.support, ∃ si ∈ s, si ≤ xi
begin refine add_monoid_algebra.mem_ideal_span_of'_image.trans _, simp_rw [le_iff_exists_add, add_comm], refl, end
lemma
mv_polynomial.mem_ideal_span_monomial_image
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/ideal.lean
[ "algebra.monoid_algebra.ideal", "data.mv_polynomial.division" ]
[ "ideal.span", "mv_polynomial" ]
`x` is in a monomial ideal generated by `s` iff every element of of its support dominates one of the generators. Note that `si ≤ xi` is analogous to saying that the monomial corresponding to `si` divides the monomial corresponding to `xi`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_ideal_span_monomial_image_iff_dvd {x : mv_polynomial σ R} {s : set (σ →₀ ℕ)} : x ∈ ideal.span ((λ s, monomial s (1 : R)) '' s) ↔ ∀ xi ∈ x.support, ∃ si ∈ s, monomial si 1 ∣ monomial xi (x.coeff xi)
begin refine mem_ideal_span_monomial_image.trans (forall₂_congr $ λ xi hxi, _), simp_rw [monomial_dvd_monomial, one_dvd, and_true, mem_support_iff.mp hxi, false_or], end
lemma
mv_polynomial.mem_ideal_span_monomial_image_iff_dvd
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/ideal.lean
[ "algebra.monoid_algebra.ideal", "data.mv_polynomial.division" ]
[ "forall₂_congr", "ideal.span", "mv_polynomial", "one_dvd" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_ideal_span_X_image {x : mv_polynomial σ R} {s : set σ} : x ∈ ideal.span (mv_polynomial.X '' s : set (mv_polynomial σ R)) ↔ ∀ m ∈ x.support, ∃ i ∈ s, (m : σ →₀ ℕ) i ≠ 0
begin have := @mem_ideal_span_monomial_image σ R _ _ ((λ i, finsupp.single i 1) '' s), rw set.image_image at this, refine this.trans _, simp [nat.one_le_iff_ne_zero], end
lemma
mv_polynomial.mem_ideal_span_X_image
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/ideal.lean
[ "algebra.monoid_algebra.ideal", "data.mv_polynomial.division" ]
[ "finsupp.single", "ideal.span", "mv_polynomial", "mv_polynomial.X", "nat.one_le_iff_ne_zero", "set.image_image" ]
`x` is in a monomial ideal generated by variables `X` iff every element of of its support has a component in `s`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
esymm (s : multiset R) (n : ℕ) : R
((s.powerset_len n).map multiset.prod).sum
def
multiset.esymm
ring_theory.mv_polynomial
src/ring_theory/mv_polynomial/symmetric.lean
[ "data.mv_polynomial.rename", "data.mv_polynomial.comm_ring", "algebra.algebra.subalgebra.basic" ]
[ "multiset", "multiset.prod" ]
The `n`th elementary symmetric function evaluated at the elements of `s`
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83