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mk_Prop : #Prop = 2 := by simp
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
mk_Prop
null
power_mul {a b c : Cardinal} : a ^ (b * c) = (a ^ b) ^ c := by rw [mul_comm b c] exact inductionOn₃ a b c fun α β γ => mk_congr <| Equiv.curry γ β α @[simp, norm_cast]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
power_mul
null
power_natCast (a : Cardinal.{u}) (n : ℕ) : a ^ (↑n : Cardinal.{u}) = a ^ n := rfl @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
power_natCast
null
lift_eq_one {a : Cardinal.{v}} : lift.{u} a = 1 ↔ a = 1 := lift_injective.eq_iff' lift_one @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_eq_one
null
lift_mul (a b : Cardinal.{u}) : lift.{v} (a * b) = lift.{v} a * lift.{v} b := inductionOn₂ a b fun _ _ => mk_congr <| Equiv.ulift.trans (Equiv.prodCongr Equiv.ulift Equiv.ulift).symm
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_mul
null
lift_two : lift.{u, v} 2 = 2 := by simp [← one_add_one_eq_two] @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_two
null
mk_set {α : Type u} : #(Set α) = 2 ^ #α := by simp [← one_add_one_eq_two, Set]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
mk_set
null
@[simp] mk_powerset {α : Type u} (s : Set α) : #(↥(𝒫 s)) = 2 ^ #(↥s) := (mk_congr (Equiv.Set.powerset s)).trans mk_set
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
mk_powerset
A variant of `Cardinal.mk_set` expressed in terms of a `Set` instead of a `Type`.
lift_two_power (a : Cardinal) : lift.{v} (2 ^ a) = 2 ^ lift.{v} a := by simp [← one_add_one_eq_two] /-! ### Order properties -/
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_two_power
null
protected zero_le : ∀ a : Cardinal, 0 ≤ a := by rintro ⟨α⟩ exact ⟨Embedding.ofIsEmpty⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
zero_le
null
private add_le_add' : ∀ {a b c d : Cardinal}, a ≤ b → c ≤ d → a + c ≤ b + d := by rintro ⟨α⟩ ⟨β⟩ ⟨γ⟩ ⟨δ⟩ ⟨e₁⟩ ⟨e₂⟩; exact ⟨e₁.sumMap e₂⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
add_le_add'
null
addLeftMono : AddLeftMono Cardinal := ⟨fun _ _ _ => add_le_add' le_rfl⟩
instance
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
addLeftMono
null
addRightMono : AddRightMono Cardinal := ⟨fun _ _ _ h => add_le_add' h le_rfl⟩
instance
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
addRightMono
null
canonicallyOrderedAdd : CanonicallyOrderedAdd Cardinal.{u} where exists_add_of_le {a b} := inductionOn₂ a b fun α β ⟨⟨f, hf⟩⟩ => have : α ⊕ ((range f)ᶜ : Set β) ≃ β := by classical exact (Equiv.sumCongr (Equiv.ofInjective f hf) (Equiv.refl _)).trans <| Equiv.Set.sumCompl (range f) ⟨#(↥(range f)ᶜ), mk_congr this.symm⟩ le_self_add a _ := (add_zero a).ge.trans <| add_le_add_left (Cardinal.zero_le _) _ le_add_self a _ := (zero_add a).ge.trans <| add_le_add_right (Cardinal.zero_le _) _
instance
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
canonicallyOrderedAdd
null
isOrderedRing : IsOrderedRing Cardinal.{u} := CanonicallyOrderedAdd.toIsOrderedRing
instance
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
isOrderedRing
null
orderBot : OrderBot Cardinal.{u} where bot := 0 bot_le := zero_le
instance
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
orderBot
null
noZeroDivisors : NoZeroDivisors Cardinal.{u} where eq_zero_or_eq_zero_of_mul_eq_zero := fun {a b} => inductionOn₂ a b fun α β => by simpa only [mul_def, mk_eq_zero_iff, isEmpty_prod] using id
instance
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
noZeroDivisors
null
zero_power_le (c : Cardinal.{u}) : (0 : Cardinal.{u}) ^ c ≤ 1 := by by_cases h : c = 0 · rw [h, power_zero] · rw [zero_power h] apply zero_le
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
zero_power_le
null
power_le_power_left : ∀ {a b c : Cardinal}, a ≠ 0 → b ≤ c → a ^ b ≤ a ^ c := by rintro ⟨α⟩ ⟨β⟩ ⟨γ⟩ hα ⟨e⟩ let ⟨a⟩ := mk_ne_zero_iff.1 hα exact ⟨@Function.Embedding.arrowCongrLeft _ _ _ ⟨a⟩ e⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
power_le_power_left
null
self_le_power (a : Cardinal) {b : Cardinal} (hb : 1 ≤ b) : a ≤ a ^ b := by rcases eq_or_ne a 0 with (rfl | ha) · exact zero_le _ · convert power_le_power_left ha hb exact (power_one a).symm
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
self_le_power
null
cantor (a : Cardinal.{u}) : a < 2 ^ a := by induction a using Cardinal.inductionOn with | _ α rw [← mk_set] refine ⟨⟨⟨singleton, fun a b => singleton_eq_singleton_iff.1⟩⟩, ?_⟩ rintro ⟨⟨f, hf⟩⟩ exact cantor_injective f hf
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
cantor
**Cantor's theorem**
power_le_max_power_one {a b c : Cardinal} (h : b ≤ c) : a ^ b ≤ max (a ^ c) 1 := by by_cases ha : a = 0 · simp [ha, zero_power_le] · exact (power_le_power_left ha h).trans (le_max_left _ _)
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
power_le_max_power_one
null
power_le_power_right {a b c : Cardinal} : a ≤ b → a ^ c ≤ b ^ c := inductionOn₃ a b c fun _ _ _ ⟨e⟩ => ⟨Embedding.arrowCongrRight e⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
power_le_power_right
null
power_pos {a : Cardinal} (b : Cardinal) (ha : 0 < a) : 0 < a ^ b := (power_ne_zero _ ha.ne').bot_lt
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
power_pos
null
protected lt_wf : @WellFounded Cardinal.{u} (· < ·) := ⟨fun a => by_contradiction fun h => by let ι := { c : Cardinal // ¬Acc (· < ·) c } let f : ι → Cardinal := Subtype.val haveI hι : Nonempty ι := ⟨⟨_, h⟩⟩ obtain ⟨⟨c : Cardinal, hc : ¬Acc (· < ·) c⟩, ⟨h_1 : ∀ j, (f ⟨c, hc⟩).out ↪ (f j).out⟩⟩ := Embedding.min_injective fun i => (f i).out refine hc (Acc.intro _ fun j h' => by_contradiction fun hj => h'.2 ?_) have : #_ ≤ #_ := ⟨h_1 ⟨j, hj⟩⟩ simpa only [mk_out] using this⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lt_wf
null
@[simp] sInf_empty : sInf (∅ : Set Cardinal.{u}) = 0 := dif_neg Set.not_nonempty_empty
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
sInf_empty
null
ne_zero_of_isSuccLimit {c} (h : IsSuccLimit c) : c ≠ 0 := h.ne_bot
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
ne_zero_of_isSuccLimit
Note that the successor of `c` is not the same as `c + 1` except in the case of finite `c`. -/ instance : SuccOrder Cardinal := ConditionallyCompleteLinearOrder.toSuccOrder theorem succ_def (c : Cardinal) : succ c = sInf { c' | c < c' } := dif_neg <| not_isMax c theorem succ_pos : ∀ c : Cardinal, 0 < succ c := bot_lt_succ theorem succ_ne_zero (c : Cardinal) : succ c ≠ 0 := (succ_pos _).ne' theorem add_one_le_succ (c : Cardinal.{u}) : c + 1 ≤ succ c := by have : Set.Nonempty { c' | c < c' } := exists_gt c simp_rw [succ_def, le_csInf_iff'' this, mem_setOf] intro b hlt rcases b, c with ⟨⟨β⟩, ⟨γ⟩⟩ obtain ⟨f⟩ := le_of_lt hlt have : ¬Surjective f := fun hn => (not_le_of_gt hlt) (mk_le_of_surjective hn) simp only [Surjective, not_forall] at this rcases this with ⟨b, hb⟩ calc #γ + 1 = #(Option γ) := mk_option.symm _ ≤ #β := (f.optionElim b hb).cardinal_le @[simp] theorem lift_succ (a) : lift.{v, u} (succ a) = succ (lift.{v, u} a) := le_antisymm (le_of_not_gt fun h => by rcases lt_lift_iff.1 h with ⟨b, h, e⟩ rw [lt_succ_iff, ← lift_le, e] at h exact h.not_gt (lt_succ _)) (succ_le_of_lt <| lift_lt.2 <| lt_succ a) /-! ### Limit cardinals
isSuccPrelimit_zero : IsSuccPrelimit (0 : Cardinal) := isSuccPrelimit_bot
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
isSuccPrelimit_zero
null
protected isSuccLimit_iff {c : Cardinal} : IsSuccLimit c ↔ c ≠ 0 ∧ IsSuccPrelimit c := isSuccLimit_iff @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
isSuccLimit_iff
null
protected not_isSuccLimit_zero : ¬ IsSuccLimit (0 : Cardinal) := not_isSuccLimit_bot
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
not_isSuccLimit_zero
null
IsStrongLimit (c : Cardinal) : Prop where ne_zero : c ≠ 0 two_power_lt ⦃x⦄ : x < c → 2 ^ x < c
structure
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
IsStrongLimit
A cardinal is a strong limit if it is not zero and it is closed under powersets. Note that `ℵ₀` is a strong limit by this definition.
protected IsStrongLimit.isSuccLimit {c} (H : IsStrongLimit c) : IsSuccLimit c := by rw [Cardinal.isSuccLimit_iff] exact ⟨H.ne_zero, isSuccPrelimit_of_succ_lt fun x h ↦ (succ_le_of_lt <| cantor x).trans_lt (H.two_power_lt h)⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
IsStrongLimit.isSuccLimit
null
protected IsStrongLimit.isSuccPrelimit {c} (H : IsStrongLimit c) : IsSuccPrelimit c := H.isSuccLimit.isSuccPrelimit @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
IsStrongLimit.isSuccPrelimit
null
not_isStrongLimit_zero : ¬ IsStrongLimit (0 : Cardinal) := fun h ↦ h.ne_zero rfl /-! ### Indexed cardinal `sum` -/
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
not_isStrongLimit_zero
null
le_sum {ι} (f : ι → Cardinal) (i) : f i ≤ sum f := by rw [← Quotient.out_eq (f i)] exact ⟨⟨fun a => ⟨i, a⟩, fun a b h => by injection h⟩⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
le_sum
null
iSup_le_sum {ι} (f : ι → Cardinal) : iSup f ≤ sum f := ciSup_le' <| le_sum _ @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
iSup_le_sum
null
sum_add_distrib {ι} (f g : ι → Cardinal) : sum (f + g) = sum f + sum g := by have := mk_congr (Equiv.sigmaSumDistrib (Quotient.out ∘ f) (Quotient.out ∘ g)) simp only [comp_apply, mk_sigma, mk_sum, mk_out, lift_id] at this exact this @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
sum_add_distrib
null
sum_add_distrib' {ι} (f g : ι → Cardinal) : (Cardinal.sum fun i => f i + g i) = sum f + sum g := sum_add_distrib f g
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
sum_add_distrib'
null
sum_le_sum {ι} (f g : ι → Cardinal) (H : ∀ i, f i ≤ g i) : sum f ≤ sum g := ⟨(Embedding.refl _).sigmaMap fun i => Classical.choice <| by have := H i; rwa [← Quot.out_eq (f i), ← Quot.out_eq (g i)] at this⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
sum_le_sum
null
mk_le_mk_mul_of_mk_preimage_le {c : Cardinal} (f : α → β) (hf : ∀ b : β, #(f ⁻¹' {b}) ≤ c) : #α ≤ #β * c := by simpa only [← mk_congr (@Equiv.sigmaFiberEquiv α β f), mk_sigma, ← sum_const'] using sum_le_sum _ _ hf
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
mk_le_mk_mul_of_mk_preimage_le
null
lift_mk_le_lift_mk_mul_of_lift_mk_preimage_le {α : Type u} {β : Type v} {c : Cardinal} (f : α → β) (hf : ∀ b : β, lift.{v} #(f ⁻¹' {b}) ≤ c) : lift.{v} #α ≤ lift.{u} #β * c := (mk_le_mk_mul_of_mk_preimage_le fun x : ULift.{v} α => ULift.up.{u} (f x.1)) <| ULift.forall.2 fun b => (mk_congr <| (Equiv.ulift.image _).trans (Equiv.trans (by rw [Equiv.image_eq_preimage] simp only [preimage, mem_singleton_iff, ULift.up_inj, mem_setOf_eq, coe_setOf] exact Equiv.refl _) Equiv.ulift.symm)).trans_le (hf b)
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_mk_le_lift_mk_mul_of_lift_mk_preimage_le
null
nonempty_embedding_to_cardinal : Nonempty (α ↪ Cardinal.{u}) := (Embedding.total _ _).resolve_left fun ⟨⟨f, hf⟩⟩ => let g : α → Cardinal.{u} := invFun f let ⟨x, (hx : g x = 2 ^ sum g)⟩ := invFun_surjective hf (2 ^ sum g) have : g x ≤ sum g := le_sum.{u, u} g x not_le_of_gt (by rw [hx]; exact cantor _) this
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
nonempty_embedding_to_cardinal
null
embeddingToCardinal : α ↪ Cardinal.{u} := Classical.choice nonempty_embedding_to_cardinal
def
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
embeddingToCardinal
An embedding of any type to the set of cardinals in its universe.
WellOrderingRel : α → α → Prop := embeddingToCardinal ⁻¹'o (· < ·)
def
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
WellOrderingRel
Any type can be endowed with a well order, obtained by pulling back the well order over cardinals by some embedding.
WellOrderingRel.isWellOrder : IsWellOrder α WellOrderingRel := (RelEmbedding.preimage _ _).isWellOrder
instance
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
WellOrderingRel.isWellOrder
null
IsWellOrder.subtype_nonempty : Nonempty { r // IsWellOrder α r } := ⟨⟨WellOrderingRel, inferInstance⟩⟩ variable (α) in
instance
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
IsWellOrder.subtype_nonempty
null
exists_wellOrder : ∃ (_ : LinearOrder α), WellFoundedLT α := by classical exact ⟨linearOrderOfSTO WellOrderingRel, WellOrderingRel.isWellOrder.toIsWellFounded⟩
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
exists_wellOrder
The **well-ordering theorem** (or **Zermelo's theorem**): every type has a well-order
exists_eq_of_iSup_eq_of_not_isSuccPrelimit {ι : Type u} (f : ι → Cardinal.{v}) (ω : Cardinal.{v}) (hω : ¬ IsSuccPrelimit ω) (h : ⨆ i : ι, f i = ω) : ∃ i, f i = ω := by subst h suffices BddAbove (range f) from (isLUB_csSup' this).mem_of_not_isSuccPrelimit hω contrapose! hω with hf rw [iSup, csSup_of_not_bddAbove hf, csSup_empty] exact isSuccPrelimit_bot
lemma
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
exists_eq_of_iSup_eq_of_not_isSuccPrelimit
null
exists_eq_of_iSup_eq_of_not_isSuccLimit {ι : Type u} [hι : Nonempty ι] (f : ι → Cardinal.{v}) (hf : BddAbove (range f)) {c : Cardinal.{v}} (hc : ¬ IsSuccLimit c) (h : ⨆ i, f i = c) : ∃ i, f i = c := by rw [Cardinal.isSuccLimit_iff] at hc refine (not_and_or.mp hc).elim (fun e ↦ ⟨hι.some, ?_⟩) (Cardinal.exists_eq_of_iSup_eq_of_not_isSuccPrelimit.{u, v} f c · h) cases not_not.mp e rw [← le_zero_iff] at h ⊢ exact (le_ciSup hf _).trans h /-! ### Indexed cardinal `prod` -/
lemma
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
exists_eq_of_iSup_eq_of_not_isSuccLimit
null
sum_lt_prod {ι} (f g : ι → Cardinal) (H : ∀ i, f i < g i) : sum f < prod g := lt_of_not_ge fun ⟨F⟩ => by have : Inhabited (∀ i : ι, (g i).out) := by refine ⟨fun i => Classical.choice <| mk_ne_zero_iff.1 ?_⟩ rw [mk_out] exact (H i).ne_bot let G := invFun F have sG : Surjective G := invFun_surjective F.2 choose C hc using show ∀ i, ∃ b, ∀ a, G ⟨i, a⟩ i ≠ b by intro i simp only [not_exists.symm, not_forall.symm] refine fun h => (H i).not_ge ?_ rw [← mk_out (f i), ← mk_out (g i)] exact ⟨Embedding.ofSurjective _ h⟩ let ⟨⟨i, a⟩, h⟩ := sG C exact hc i a (congr_fun h _)
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
sum_lt_prod
**König's theorem**
prod_le_prod {ι} (f g : ι → Cardinal) (H : ∀ i, f i ≤ g i) : prod f ≤ prod g := ⟨Embedding.piCongrRight fun i => Classical.choice <| by have := H i; rwa [← mk_out (f i), ← mk_out (g i)] at this⟩ /-! ### The first infinite cardinal `aleph0` -/
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
prod_le_prod
null
aleph0_pos : 0 < ℵ₀ := pos_iff_ne_zero.2 aleph0_ne_zero @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
aleph0_pos
null
aleph0_le_lift {c : Cardinal.{u}} : ℵ₀ ≤ lift.{v} c ↔ ℵ₀ ≤ c := by simpa using lift_le (a := ℵ₀) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
aleph0_le_lift
null
lift_le_aleph0 {c : Cardinal.{u}} : lift.{v} c ≤ ℵ₀ ↔ c ≤ ℵ₀ := by simpa using lift_le (b := ℵ₀) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_le_aleph0
null
aleph0_lt_lift {c : Cardinal.{u}} : ℵ₀ < lift.{v} c ↔ ℵ₀ < c := by simpa using lift_lt (a := ℵ₀) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
aleph0_lt_lift
null
lift_lt_aleph0 {c : Cardinal.{u}} : lift.{v} c < ℵ₀ ↔ c < ℵ₀ := by simpa using lift_lt (b := ℵ₀) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_lt_aleph0
null
aleph0_eq_lift {c : Cardinal.{u}} : ℵ₀ = lift.{v} c ↔ ℵ₀ = c := by simpa using lift_inj (a := ℵ₀) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
aleph0_eq_lift
null
lift_eq_aleph0 {c : Cardinal.{u}} : lift.{v} c = ℵ₀ ↔ c = ℵ₀ := by simpa using lift_inj (b := ℵ₀) /-! ### Properties about the cast from `ℕ` -/
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_eq_aleph0
null
mk_fin (n : ℕ) : #(Fin n) = n := by simp @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
mk_fin
null
lift_natCast (n : ℕ) : lift.{u} (n : Cardinal.{v}) = n := by induction n <;> simp [*] @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_natCast
null
lift_ofNat (n : ℕ) [n.AtLeastTwo] : lift.{u} (ofNat(n) : Cardinal.{v}) = OfNat.ofNat n := lift_natCast n @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_ofNat
null
lift_eq_nat_iff {a : Cardinal.{u}} {n : ℕ} : lift.{v} a = n ↔ a = n := lift_injective.eq_iff' (lift_natCast n) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_eq_nat_iff
null
lift_eq_ofNat_iff {a : Cardinal.{u}} {n : ℕ} [n.AtLeastTwo] : lift.{v} a = ofNat(n) ↔ a = OfNat.ofNat n := lift_eq_nat_iff @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_eq_ofNat_iff
null
nat_eq_lift_iff {n : ℕ} {a : Cardinal.{u}} : (n : Cardinal) = lift.{v} a ↔ (n : Cardinal) = a := by rw [← lift_natCast.{v,u} n, lift_inj] @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
nat_eq_lift_iff
null
zero_eq_lift_iff {a : Cardinal.{u}} : (0 : Cardinal) = lift.{v} a ↔ 0 = a := by simpa using nat_eq_lift_iff (n := 0) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
zero_eq_lift_iff
null
one_eq_lift_iff {a : Cardinal.{u}} : (1 : Cardinal) = lift.{v} a ↔ 1 = a := by simpa using nat_eq_lift_iff (n := 1) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
one_eq_lift_iff
null
ofNat_eq_lift_iff {a : Cardinal.{u}} {n : ℕ} [n.AtLeastTwo] : (ofNat(n) : Cardinal) = lift.{v} a ↔ (OfNat.ofNat n : Cardinal) = a := nat_eq_lift_iff @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
ofNat_eq_lift_iff
null
lift_le_nat_iff {a : Cardinal.{u}} {n : ℕ} : lift.{v} a ≤ n ↔ a ≤ n := by rw [← lift_natCast.{v,u}, lift_le] @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_le_nat_iff
null
lift_le_one_iff {a : Cardinal.{u}} : lift.{v} a ≤ 1 ↔ a ≤ 1 := by simpa using lift_le_nat_iff (n := 1) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_le_one_iff
null
lift_le_ofNat_iff {a : Cardinal.{u}} {n : ℕ} [n.AtLeastTwo] : lift.{v} a ≤ ofNat(n) ↔ a ≤ OfNat.ofNat n := lift_le_nat_iff @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_le_ofNat_iff
null
nat_le_lift_iff {n : ℕ} {a : Cardinal.{u}} : n ≤ lift.{v} a ↔ n ≤ a := by rw [← lift_natCast.{v,u}, lift_le] @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
nat_le_lift_iff
null
one_le_lift_iff {a : Cardinal.{u}} : (1 : Cardinal) ≤ lift.{v} a ↔ 1 ≤ a := by simpa using nat_le_lift_iff (n := 1) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
one_le_lift_iff
null
ofNat_le_lift_iff {a : Cardinal.{u}} {n : ℕ} [n.AtLeastTwo] : (ofNat(n) : Cardinal) ≤ lift.{v} a ↔ (OfNat.ofNat n : Cardinal) ≤ a := nat_le_lift_iff @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
ofNat_le_lift_iff
null
lift_lt_nat_iff {a : Cardinal.{u}} {n : ℕ} : lift.{v} a < n ↔ a < n := by rw [← lift_natCast.{v,u}, lift_lt] @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_lt_nat_iff
null
lift_lt_ofNat_iff {a : Cardinal.{u}} {n : ℕ} [n.AtLeastTwo] : lift.{v} a < ofNat(n) ↔ a < OfNat.ofNat n := lift_lt_nat_iff @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
lift_lt_ofNat_iff
null
nat_lt_lift_iff {n : ℕ} {a : Cardinal.{u}} : n < lift.{v} a ↔ n < a := by rw [← lift_natCast.{v,u}, lift_lt] @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
nat_lt_lift_iff
null
zero_lt_lift_iff {a : Cardinal.{u}} : (0 : Cardinal) < lift.{v} a ↔ 0 < a := by simpa using nat_lt_lift_iff (n := 0) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
zero_lt_lift_iff
null
one_lt_lift_iff {a : Cardinal.{u}} : (1 : Cardinal) < lift.{v} a ↔ 1 < a := by simpa using nat_lt_lift_iff (n := 1) @[simp]
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
one_lt_lift_iff
null
ofNat_lt_lift_iff {a : Cardinal.{u}} {n : ℕ} [n.AtLeastTwo] : (ofNat(n) : Cardinal) < lift.{v} a ↔ (OfNat.ofNat n : Cardinal) < a := nat_lt_lift_iff
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
ofNat_lt_lift_iff
null
mk_coe_finset {α : Type u} {s : Finset α} : #s = ↑(Finset.card s) := by simp
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
mk_coe_finset
null
card_le_of_finset {α} (s : Finset α) : (s.card : Cardinal) ≤ #α := @mk_coe_finset _ s ▸ mk_set_le _
theorem
SetTheory
[ "Mathlib.Algebra.Order.GroupWithZero.Canonical", "Mathlib.Algebra.Order.Ring.Canonical", "Mathlib.Data.Fintype.Option", "Mathlib.Order.InitialSeg", "Mathlib.Order.Nat", "Mathlib.Order.SuccPred.CompleteLinearOrder", "Mathlib.SetTheory.Cardinal.Defs", "Mathlib.SetTheory.Cardinal.SchroederBernstein" ]
Mathlib/SetTheory/Cardinal/Order.lean
card_le_of_finset
null
mk_iUnion_Ordinal_lift_le_of_le {β : Type v} {o : Ordinal.{u}} {c : Cardinal.{v}} (ho : lift.{v} o.card ≤ lift.{u} c) (hc : ℵ₀ ≤ c) (A : Ordinal → Set β) (hA : ∀ j < o, #(A j) ≤ c) : #(⋃ j < o, A j) ≤ c := by simp_rw [← mem_Iio, biUnion_eq_iUnion, iUnion, iSup, ← o.enumIsoToType.symm.surjective.range_comp] rw [← lift_le.{u}] apply ((mk_iUnion_le_lift _).trans _).trans_eq (mul_eq_self (aleph0_le_lift.2 hc)) rw [mk_toType] refine mul_le_mul' ho (ciSup_le' ?_) intro i simpa using hA _ (o.enumIsoToType.symm i).2
lemma
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
mk_iUnion_Ordinal_lift_le_of_le
Bounds the cardinal of an ordinal-indexed union of sets.
mk_iUnion_Ordinal_le_of_le {β : Type*} {o : Ordinal} {c : Cardinal} (ho : o.card ≤ c) (hc : ℵ₀ ≤ c) (A : Ordinal → Set β) (hA : ∀ j < o, #(A j) ≤ c) : #(⋃ j < o, A j) ≤ c := by apply mk_iUnion_Ordinal_lift_le_of_le _ hc A hA rwa [Cardinal.lift_le]
lemma
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
mk_iUnion_Ordinal_le_of_le
null
lift_card_iSup_le_sum_card {ι : Type u} [Small.{v} ι] (f : ι → Ordinal.{v}) : Cardinal.lift.{u} (⨆ i, f i).card ≤ Cardinal.sum fun i ↦ (f i).card := by simp_rw [← mk_toType] rw [← mk_sigma, ← Cardinal.lift_id'.{v} #(Σ _, _), ← Cardinal.lift_umax.{v, u}] apply lift_mk_le_lift_mk_of_surjective (f := enumIsoToType _ ∘ (⟨(enumIsoToType _).symm ·.2, (mem_Iio.mp ((enumIsoToType _).symm _).2).trans_le (Ordinal.le_iSup _ _)⟩)) rw [EquivLike.comp_surjective] rintro ⟨x, hx⟩ obtain ⟨i, hi⟩ := Ordinal.lt_iSup_iff.mp hx exact ⟨⟨i, enumIsoToType _ ⟨x, hi⟩⟩, by simp⟩
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
lift_card_iSup_le_sum_card
null
card_iSup_le_sum_card {ι : Type u} (f : ι → Ordinal.{max u v}) : (⨆ i, f i).card ≤ Cardinal.sum (fun i ↦ (f i).card) := by have := lift_card_iSup_le_sum_card f rwa [Cardinal.lift_id'] at this
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_iSup_le_sum_card
null
card_iSup_Iio_le_sum_card {o : Ordinal.{u}} (f : Iio o → Ordinal.{max u v}) : (⨆ a : Iio o, f a).card ≤ Cardinal.sum fun i ↦ (f ((enumIsoToType o).symm i)).card := by apply le_of_eq_of_le (congr_arg _ _).symm (card_iSup_le_sum_card _) simpa using (enumIsoToType o).symm.iSup_comp (g := fun x ↦ f x)
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_iSup_Iio_le_sum_card
null
card_iSup_Iio_le_card_mul_iSup {o : Ordinal.{u}} (f : Iio o → Ordinal.{max u v}) : (⨆ a : Iio o, f a).card ≤ Cardinal.lift.{v} o.card * ⨆ a : Iio o, (f a).card := by apply (card_iSup_Iio_le_sum_card f).trans convert ← sum_le_iSup_lift _ · exact mk_toType o · exact (enumIsoToType o).symm.iSup_comp (g := fun x ↦ (f x).card)
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_iSup_Iio_le_card_mul_iSup
null
card_opow_le_of_omega0_le_left {a : Ordinal} (ha : ω ≤ a) (b : Ordinal) : (a ^ b).card ≤ max a.card b.card := by refine limitRecOn b ?_ ?_ ?_ · simpa using one_lt_omega0.le.trans ha · intro b IH rw [opow_succ, card_mul, card_succ, Cardinal.mul_eq_max_of_aleph0_le_right, max_comm] · grw [IH] rw [← max_assoc, max_self] grw [← le_self_add] · rw [ne_eq, card_eq_zero, opow_eq_zero] rintro ⟨rfl, -⟩ cases omega0_pos.not_ge ha · rwa [aleph0_le_card] · intro b hb IH rw [(isNormal_opow (one_lt_omega0.trans_le ha)).apply_of_isSuccLimit hb] apply (card_iSup_Iio_le_card_mul_iSup _).trans rw [Cardinal.lift_id, Cardinal.mul_eq_max_of_aleph0_le_right, max_comm] · apply max_le _ (le_max_right _ _) apply ciSup_le' rintro ⟨c, (hcb : c < b)⟩ grw [IH c hcb, hcb] · simpa using hb.ne_bot · refine le_ciSup_of_le ?_ ⟨1, one_lt_omega0.trans_le <| omega0_le_of_isSuccLimit hb⟩ ?_ · exact Cardinal.bddAbove_of_small _ · simpa
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_opow_le_of_omega0_le_left
null
card_opow_le_of_omega0_le_right (a : Ordinal) {b : Ordinal} (hb : ω ≤ b) : (a ^ b).card ≤ max a.card b.card := by obtain ⟨n, rfl⟩ | ha := eq_nat_or_omega0_le a · apply (card_le_card <| opow_le_opow_left b (nat_lt_omega0 n).le).trans apply (card_opow_le_of_omega0_le_left le_rfl _).trans simp [hb] · exact card_opow_le_of_omega0_le_left ha b
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_opow_le_of_omega0_le_right
null
card_opow_le (a b : Ordinal) : (a ^ b).card ≤ max ℵ₀ (max a.card b.card) := by obtain ⟨n, rfl⟩ | ha := eq_nat_or_omega0_le a · obtain ⟨m, rfl⟩ | hb := eq_nat_or_omega0_le b · rw [← natCast_opow, card_nat] exact le_max_of_le_left (nat_lt_aleph0 _).le · exact (card_opow_le_of_omega0_le_right _ hb).trans (le_max_right _ _) · exact (card_opow_le_of_omega0_le_left ha _).trans (le_max_right _ _)
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_opow_le
null
card_opow_eq_of_omega0_le_left {a b : Ordinal} (ha : ω ≤ a) (hb : 0 < b) : (a ^ b).card = max a.card b.card := by apply (card_opow_le_of_omega0_le_left ha b).antisymm (max_le _ _) <;> apply card_le_card · exact left_le_opow a hb · exact right_le_opow b (one_lt_omega0.trans_le ha)
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_opow_eq_of_omega0_le_left
null
card_opow_eq_of_omega0_le_right {a b : Ordinal} (ha : 1 < a) (hb : ω ≤ b) : (a ^ b).card = max a.card b.card := by apply (card_opow_le_of_omega0_le_right a hb).antisymm (max_le _ _) <;> apply card_le_card · exact left_le_opow a (omega0_pos.trans_le hb) · exact right_le_opow b ha
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_opow_eq_of_omega0_le_right
null
card_omega0_opow {a : Ordinal} (h : a ≠ 0) : card (ω ^ a) = max ℵ₀ a.card := by rw [card_opow_eq_of_omega0_le_left le_rfl h.bot_lt, card_omega0]
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_omega0_opow
null
card_opow_omega0 {a : Ordinal} (h : 1 < a) : card (a ^ ω) = max ℵ₀ a.card := by rw [card_opow_eq_of_omega0_le_right h le_rfl, card_omega0, max_comm]
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
card_opow_omega0
null
principal_opow_omega (o : Ordinal) : Principal (· ^ ·) (ω_ o) := by obtain rfl | ho := Ordinal.eq_zero_or_pos o · rw [omega_zero] exact principal_opow_omega0 · intro a b ha hb rw [lt_omega_iff_card_lt] at ha hb ⊢ apply (card_opow_le a b).trans_lt (max_lt _ (max_lt ha hb)) rwa [← aleph_zero, aleph_lt_aleph]
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
principal_opow_omega
null
IsInitial.principal_opow {o : Ordinal} (h : IsInitial o) (ho : ω ≤ o) : Principal (· ^ ·) o := by obtain ⟨a, rfl⟩ := mem_range_omega_iff.2 ⟨ho, h⟩ exact principal_opow_omega a
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
IsInitial.principal_opow
null
principal_opow_ord {c : Cardinal} (hc : ℵ₀ ≤ c) : Principal (· ^ ·) c.ord := by apply (isInitial_ord c).principal_opow rwa [omega0_le_ord] /-! ### Initial ordinals are principal -/
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
principal_opow_ord
null
principal_add_ord {c : Cardinal} (hc : ℵ₀ ≤ c) : Principal (· + ·) c.ord := by intro a b ha hb rw [lt_ord, card_add] at * exact add_lt_of_lt hc ha hb
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
principal_add_ord
null
IsInitial.principal_add {o : Ordinal} (h : IsInitial o) (ho : ω ≤ o) : Principal (· + ·) o := by rw [← h.ord_card] apply principal_add_ord rwa [aleph0_le_card]
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
IsInitial.principal_add
null
principal_add_omega (o : Ordinal) : Principal (· + ·) (ω_ o) := (isInitial_omega o).principal_add (omega0_le_omega o)
theorem
SetTheory
[ "Mathlib.SetTheory.Cardinal.Arithmetic", "Mathlib.SetTheory.Ordinal.Principal" ]
Mathlib/SetTheory/Cardinal/Ordinal.lean
principal_add_omega
null