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Sum.elim_map ** α : Type u_1 β : Type u_2 ε : Sort u_3 γ : Type u_4 δ : Type u_5 f₁ : α → β f₂ : β → ε g₁ : γ → δ g₂ : δ → ε x : α ⊕ γ ⊢ Sum.elim f₂ g₂ (Sum.map f₁ g₁ x) = Sum.elim (f₂ ∘ f₁) (g₂ ∘ g₁) x ** cases x <;> rfl ** Qed
Sum.isLeft_map ** α : Type u_1 β : Type u_2 γ : Type u_3 δ : Type u_4 f : α → β g : γ → δ x : α ⊕ γ ⊢ isLeft (Sum.map f g x) = isLeft x ** cases x <;> rfl ** Qed
Sum.isRight_map ** α : Type u_1 β : Type u_2 γ : Type u_3 δ : Type u_4 f : α → β g : γ → δ x : α ⊕ γ ⊢ isRight (Sum.map f g x) = isRight x ** cases x <;> rfl ** Qed
Sum.getLeft?_map ** α : Type u_1 β : Type u_2 γ : Type u_3 δ : Type u_4 f : α → β g : γ → δ x : α ⊕ γ ⊢ getLeft? (Sum.map f g x) = Option.map f (getLeft? x) ** cases x <;> rfl ** Qed
Sum.getRight?_map ** α : Type u_1 β : Type u_2 γ : Type u_3 δ : Type u_4 f : α → β g : γ → δ x : α ⊕ γ ⊢ getRight? (Sum.map f g x) = Option.map g (getRight? x) ** cases x <;> rfl ** Qed
Sum.swap_swap ** α : Type u_1 β : Type u_2 x : α ⊕ β ⊢ swap (swap x) = x ** cases x <;> rfl ** Qed
Sum.isLeft_swap ** α : Type u_1 β : Type u_2 x : α ⊕ β ⊢ isLeft (swap x) = isRight x ** cases x <;> rfl ** Qed
Sum.isRight_swap ** α : Type u_1 β : Type u_2 x : α ⊕ β ⊢ isRight (swap x) = isLeft x ** cases x <;> rfl ** Qed
Sum.getLeft?_swap ** α : Type u_1 β : Type u_2 x : α ⊕ β ⊢ getLeft? (swap x) = getRight? x ** cases x <;> rfl ** Qed
Sum.getRight?_swap ** α : Type u_1 β : Type u_2 x : α ⊕ β ⊢ getRight? (swap x) = getLeft? x ** cases x <;> rfl ** Qed
Sum.LiftRel.mono ** α✝¹ : Type u_1 α✝ : Type u_2 r₁ r₂ : α✝¹ → α✝ → Prop β✝¹ : Type u_3 β✝ : Type u_4 s₁ s₂ : β✝¹ → β✝ → Prop x : α✝¹ ⊕ β✝¹ y : α✝ ⊕ β✝ hr : ∀ (a : α✝¹) (b : α✝), r₁ a b → r₂ a b hs : ∀ (a : β✝¹) (b : β✝), s₁ a b → s₂ a b h : LiftRel r₁ s₁ x y ⊢ LiftRel r₂ s₂ x y ** cases h ** case inl α✝¹ : Type u_1 α✝ : Type u_2 r₁ r₂ : α✝¹ → α✝ → Prop β✝¹ : Type u_3 β✝ : Type u_4 s₁ s₂ : β✝¹ → β✝ → Prop hr : ∀ (a : α✝¹) (b : α✝), r₁ a b → r₂ a b hs : ∀ (a : β✝¹) (b : β✝), s₁ a b → s₂ a b a✝¹ : α✝¹ c✝ : α✝ a✝ : r₁ a✝¹ c✝ ⊢ LiftRel r₂ s₂ (inl a✝¹) (inl c✝) ** exact LiftRel.inl (hr _ _ ‹_›) ** case inr α✝¹ : Type u_1 α✝ : Type u_2 r₁ r₂ : α✝¹ → α✝ → Prop β✝¹ : Type u_3 β✝ : Type u_4 s₁ s₂ : β✝¹ → β✝ → Prop hr : ∀ (a : α✝¹) (b : α✝), r₁ a b → r₂ a b hs : ∀ (a : β✝¹) (b : β✝), s₁ a b → s₂ a b b✝ : β✝¹ d✝ : β✝ a✝ : s₁ b✝ d✝ ⊢ LiftRel r₂ s₂ (inr b✝) (inr d✝) ** exact LiftRel.inr (hs _ _ ‹_›) ** Qed
Sum.LiftRel.swap ** α✝¹ : Type u_1 α✝ : Type u_2 r : α✝¹ → α✝ → Prop β✝¹ : Type u_3 β✝ : Type u_4 s : β✝¹ → β✝ → Prop x : α✝¹ ⊕ β✝¹ y : α✝ ⊕ β✝ h : LiftRel r s x y ⊢ LiftRel s r (swap x) (swap y) ** cases h ** case inl α✝¹ : Type u_1 α✝ : Type u_2 r : α✝¹ → α✝ → Prop β✝¹ : Type u_3 β✝ : Type u_4 s : β✝¹ → β✝ → Prop a✝¹ : α✝¹ c✝ : α✝ a✝ : r a✝¹ c✝ ⊢ LiftRel s r (swap (inl a✝¹)) (swap (inl c✝)) ** exact LiftRel.inr ‹_› ** case inr α✝¹ : Type u_1 α✝ : Type u_2 r : α✝¹ → α✝ → Prop β✝¹ : Type u_3 β✝ : Type u_4 s : β✝¹ → β✝ → Prop b✝ : β✝¹ d✝ : β✝ a✝ : s b✝ d✝ ⊢ LiftRel s r (swap (inr b✝)) (swap (inr d✝)) ** exact LiftRel.inl ‹_› ** Qed
Sum.LiftRel.lex ** α : Type u_1 β : Type u_2 r : α → α → Prop s : β → β → Prop a b : α ⊕ β h : LiftRel r s a b ⊢ Lex r s a b ** cases h ** case inl α : Type u_1 β : Type u_2 r : α → α → Prop s : β → β → Prop a✝¹ c✝ : α a✝ : r a✝¹ c✝ ⊢ Lex r s (inl a✝¹) (inl c✝) ** exact Lex.inl ‹_› ** case inr α : Type u_1 β : Type u_2 r : α → α → Prop s : β → β → Prop b✝ d✝ : β a✝ : s b✝ d✝ ⊢ Lex r s (inr b✝) (inr d✝) ** exact Lex.inr ‹_› ** Qed
Sum.Lex.mono ** α✝ : Type u_1 r₁ r₂ : α✝ → α✝ → Prop β✝ : Type u_2 s₁ s₂ : β✝ → β✝ → Prop x y : α✝ ⊕ β✝ hr : ∀ (a b : α✝), r₁ a b → r₂ a b hs : ∀ (a b : β✝), s₁ a b → s₂ a b h : Lex r₁ s₁ x y ⊢ Lex r₂ s₂ x y ** cases h ** case inl α✝ : Type u_1 r₁ r₂ : α✝ → α✝ → Prop β✝ : Type u_2 s₁ s₂ : β✝ → β✝ → Prop hr : ∀ (a b : α✝), r₁ a b → r₂ a b hs : ∀ (a b : β✝), s₁ a b → s₂ a b a₁✝ a₂✝ : α✝ h✝ : r₁ a₁✝ a₂✝ ⊢ Lex r₂ s₂ (inl a₁✝) (inl a₂✝) ** exact Lex.inl (hr _ _ ‹_›) ** case inr α✝ : Type u_1 r₁ r₂ : α✝ → α✝ → Prop β✝ : Type u_2 s₁ s₂ : β✝ → β✝ → Prop hr : ∀ (a b : α✝), r₁ a b → r₂ a b hs : ∀ (a b : β✝), s₁ a b → s₂ a b b₁✝ b₂✝ : β✝ h✝ : s₁ b₁✝ b₂✝ ⊢ Lex r₂ s₂ (inr b₁✝) (inr b₂✝) ** exact Lex.inr (hs _ _ ‹_›) ** case sep α✝ : Type u_1 r₁ r₂ : α✝ → α✝ → Prop β✝ : Type u_2 s₁ s₂ : β✝ → β✝ → Prop hr : ∀ (a b : α✝), r₁ a b → r₂ a b hs : ∀ (a b : β✝), s₁ a b → s₂ a b a✝ : α✝ b✝ : β✝ ⊢ Lex r₂ s₂ (inl a✝) (inr b✝) ** exact Lex.sep _ _ ** Qed
Sum.lex_acc_inl ** α✝ : Type u_1 r : α✝ → α✝ → Prop a : α✝ β✝ : Type u_2 s : β✝ → β✝ → Prop aca : Acc r a ⊢ Acc (Lex r s) (inl a) ** induction aca with | intro _ _ IH => constructor intro y h cases h with | inl h' => exact IH _ h' ** case intro α✝ : Type u_1 r : α✝ → α✝ → Prop a : α✝ β✝ : Type u_2 s : β✝ → β✝ → Prop x✝ : α✝ h✝ : ∀ (y : α✝), r y x✝ → Acc r y IH : ∀ (y : α✝), r y x✝ → Acc (Lex r s) (inl y) ⊢ Acc (Lex r s) (inl x✝) ** constructor ** case intro.h α✝ : Type u_1 r : α✝ → α✝ → Prop a : α✝ β✝ : Type u_2 s : β✝ → β✝ → Prop x✝ : α✝ h✝ : ∀ (y : α✝), r y x✝ → Acc r y IH : ∀ (y : α✝), r y x✝ → Acc (Lex r s) (inl y) ⊢ ∀ (y : α✝ ⊕ β✝), Lex r s y (inl x✝) → Acc (Lex r s) y ** intro y h ** case intro.h α✝ : Type u_1 r : α✝ → α✝ → Prop a : α✝ β✝ : Type u_2 s : β✝ → β✝ → Prop x✝ : α✝ h✝ : ∀ (y : α✝), r y x✝ → Acc r y IH : ∀ (y : α✝), r y x✝ → Acc (Lex r s) (inl y) y : α✝ ⊕ β✝ h : Lex r s y (inl x✝) ⊢ Acc (Lex r s) y ** cases h with | inl h' => exact IH _ h' ** case intro.h.inl α✝ : Type u_1 r : α✝ → α✝ → Prop a : α✝ β✝ : Type u_2 s : β✝ → β✝ → Prop x✝ : α✝ h✝ : ∀ (y : α✝), r y x✝ → Acc r y IH : ∀ (y : α✝), r y x✝ → Acc (Lex r s) (inl y) a₁✝ : α✝ h' : r a₁✝ x✝ ⊢ Acc (Lex r s) (inl a₁✝) ** exact IH _ h' ** Qed
Sum.lex_acc_inr ** α✝ : Type u_1 r : α✝ → α✝ → Prop β✝ : Type u_2 s : β✝ → β✝ → Prop aca : ∀ (a : α✝), Acc (Lex r s) (inl a) b : β✝ acb : Acc s b ⊢ Acc (Lex r s) (inr b) ** induction acb with | intro _ _ IH => constructor intro y h cases h with | inr h' => exact IH _ h' | sep => exact aca _ ** case intro α✝ : Type u_1 r : α✝ → α✝ → Prop β✝ : Type u_2 s : β✝ → β✝ → Prop aca : ∀ (a : α✝), Acc (Lex r s) (inl a) b x✝ : β✝ h✝ : ∀ (y : β✝), s y x✝ → Acc s y IH : ∀ (y : β✝), s y x✝ → Acc (Lex r s) (inr y) ⊢ Acc (Lex r s) (inr x✝) ** constructor ** case intro.h α✝ : Type u_1 r : α✝ → α✝ → Prop β✝ : Type u_2 s : β✝ → β✝ → Prop aca : ∀ (a : α✝), Acc (Lex r s) (inl a) b x✝ : β✝ h✝ : ∀ (y : β✝), s y x✝ → Acc s y IH : ∀ (y : β✝), s y x✝ → Acc (Lex r s) (inr y) ⊢ ∀ (y : α✝ ⊕ β✝), Lex r s y (inr x✝) → Acc (Lex r s) y ** intro y h ** case intro.h α✝ : Type u_1 r : α✝ → α✝ → Prop β✝ : Type u_2 s : β✝ → β✝ → Prop aca : ∀ (a : α✝), Acc (Lex r s) (inl a) b x✝ : β✝ h✝ : ∀ (y : β✝), s y x✝ → Acc s y IH : ∀ (y : β✝), s y x✝ → Acc (Lex r s) (inr y) y : α✝ ⊕ β✝ h : Lex r s y (inr x✝) ⊢ Acc (Lex r s) y ** cases h with | inr h' => exact IH _ h' | sep => exact aca _ ** case intro.h.inr α✝ : Type u_1 r : α✝ → α✝ → Prop β✝ : Type u_2 s : β✝ → β✝ → Prop aca : ∀ (a : α✝), Acc (Lex r s) (inl a) b x✝ : β✝ h✝ : ∀ (y : β✝), s y x✝ → Acc s y IH : ∀ (y : β✝), s y x✝ → Acc (Lex r s) (inr y) b₁✝ : β✝ h' : s b₁✝ x✝ ⊢ Acc (Lex r s) (inr b₁✝) ** exact IH _ h' ** case intro.h.sep α✝ : Type u_1 r : α✝ → α✝ → Prop β✝ : Type u_2 s : β✝ → β✝ → Prop aca : ∀ (a : α✝), Acc (Lex r s) (inl a) b x✝ : β✝ h✝ : ∀ (y : β✝), s y x✝ → Acc s y IH : ∀ (y : β✝), s y x✝ → Acc (Lex r s) (inr y) a✝ : α✝ ⊢ Acc (Lex r s) (inl a✝) ** exact aca _ ** Qed
Sum.elim_const_const ** γ : Sort u_1 α : Type u_2 β : Type u_3 c : γ ⊢ Sum.elim (const α c) (const β c) = const (α ⊕ β) c ** ext x ** case h γ : Sort u_1 α : Type u_2 β : Type u_3 c : γ x : α ⊕ β ⊢ Sum.elim (const α c) (const β c) x = const (α ⊕ β) c x ** cases x <;> rfl ** Qed
Std.AssocList.isEmpty_eq ** α : Type u_1 β : Type u_2 l : AssocList α β ⊢ isEmpty l = List.isEmpty (toList l) ** cases l <;> simp [*, isEmpty, List.isEmpty] ** Qed
Std.AssocList.foldlM_eq ** m : Type u_1 → Type u_2 δ : Type u_1 α : Type u_3 β : Type u_4 inst✝ : Monad m f : δ → α → β → m δ init : δ l : AssocList α β ⊢ foldlM f init l = List.foldlM (fun d x => match x with | (a, b) => f d a b) init (toList l) ** induction l generalizing init <;> simp [*, foldlM] ** Qed
Std.AssocList.toList_eq_toListTR ** ⊢ @toList = @toListTR ** funext α β as ** case h.h.h α : Type u_2 β : Type u_1 as : AssocList α β ⊢ toList as = toListTR as ** simp [toListTR] ** case h.h.h α : Type u_2 β : Type u_1 as : AssocList α β ⊢ toList as = (List.foldl (fun d x => Array.push d (x.fst, x.snd)) #[] (toList as)).data ** exact .symm <| (Array.foldl_data_eq_map (toList as) _ id).trans (List.map_id _) ** Qed
Std.AssocList.forM_eq ** m : Type u_1 → Type u_2 α : Type u_3 β : Type u_4 inst✝ : Monad m f : α → β → m PUnit l : AssocList α β ⊢ forM f l = List.forM (toList l) fun x => match x with | (a, b) => f a b ** induction l <;> simp [*, forM] ** Qed
Std.AssocList.findEntryP?_eq ** α : Type u_1 β : Type u_2 p : α → β → Bool l : AssocList α β ⊢ findEntryP? p l = List.find? (fun x => match x with | (a, b) => p a b) (toList l) ** induction l <;> simp [findEntryP?, List.find?_cons] ** case cons α : Type u_1 β : Type u_2 p : α → β → Bool key✝ : α value✝ : β tail✝ : AssocList α β tail_ih✝ : findEntryP? p tail✝ = List.find? (fun x => match x with | (a, b) => p a b) (toList tail✝) ⊢ (bif p key✝ value✝ then some (key✝, value✝) else findEntryP? p tail✝) = match p key✝ value✝ with | true => some (key✝, value✝) | false => List.find? (fun x => p x.fst x.snd) (toList tail✝) ** split <;> simp [*] ** Qed
Std.AssocList.find?_eq_findEntry? ** α : Type u_1 β : Type u_2 inst✝ : BEq α a : α l : AssocList α β ⊢ find? a l = Option.map (fun x => x.snd) (findEntry? a l) ** induction l <;> simp [find?, List.find?_cons] ** case cons α : Type u_1 β : Type u_2 inst✝ : BEq α a key✝ : α value✝ : β tail✝ : AssocList α β tail_ih✝ : find? a tail✝ = Option.map (fun x => x.snd) (findEntry? a tail✝) ⊢ (match key✝ == a with | true => some value✝ | false => find? a tail✝) = Option.map (fun x => x.snd) (match key✝ == a with | true => some (key✝, value✝) | false => List.find? (fun x => x.fst == a) (toList tail✝)) ** split <;> simp [*] ** Qed
Std.AssocList.any_eq ** α : Type u_1 β : Type u_2 p : α → β → Bool l : AssocList α β ⊢ any p l = List.any (toList l) fun x => match x with | (a, b) => p a b ** induction l <;> simp [any, *] ** Qed
Std.AssocList.all_eq ** α : Type u_1 β : Type u_2 p : α → β → Bool l : AssocList α β ⊢ all p l = List.all (toList l) fun x => match x with | (a, b) => p a b ** induction l <;> simp [all, *] ** Qed
Std.AssocList.contains_eq ** α : Type u_1 β : Type u_2 inst✝ : BEq α a : α l : AssocList α β ⊢ contains a l = List.any (toList l) fun x => x.fst == a ** induction l <;> simp [*, contains] ** Qed
Std.AssocList.replace_toList ** α : Type u_1 β : Type u_2 inst✝ : BEq α a : α b : β l : AssocList α β ⊢ toList (replace a b l) = List.replaceF (fun x => bif x.fst == a then some (a, b) else none) (toList l) ** induction l <;> simp [replace] ** case cons α : Type u_1 β : Type u_2 inst✝ : BEq α a : α b : β key✝ : α value✝ : β tail✝ : AssocList α β tail_ih✝ : toList (replace a b tail✝) = List.replaceF (fun x => bif x.fst == a then some (a, b) else none) (toList tail✝) ⊢ toList (match key✝ == a with | true => cons a b tail✝ | false => cons key✝ value✝ (replace a b tail✝)) = match bif key✝ == a then some (a, b) else none with | none => (key✝, value✝) :: List.replaceF (fun x => bif x.fst == a then some (a, b) else none) (toList tail✝) | some a => a :: toList tail✝ ** split <;> simp [*] ** Qed
List.toAssocList_toList ** α : Type u_1 β : Type u_2 l : List (α × β) ⊢ toList (List.toAssocList l) = l ** induction l <;> simp [*] ** Qed
Std.AssocList.toList_toAssocList ** α : Type u_1 β : Type u_2 l : AssocList α β ⊢ List.toAssocList (toList l) = l ** induction l <;> simp [*] ** Qed
Int.subNatNat_of_sub_eq_zero ** m n : Nat h : n - m = 0 ⊢ subNatNat m n = ↑(m - n) ** rw [subNatNat, h, ofNat_eq_coe] ** Qed
Int.subNatNat_of_sub_eq_succ ** m n k : Nat h : n - m = succ k ⊢ subNatNat m n = -[k+1] ** rw [subNatNat, h] ** Qed
Int.negSucc_inj ** m n : Nat H : m = n ⊢ -[m+1] = -[n+1] ** simp [H] ** Qed
Int.neg_inj ** a b : Int h : -a = -b ⊢ a = b ** rw [← Int.neg_neg a, ← Int.neg_neg b, h] ** Qed
Int.subNatNat_elim ** m n : Nat motive : Nat → Nat → Int → Prop hp : ∀ (i n : Nat), motive (n + i) n ↑i hn : ∀ (i m : Nat), motive m (m + i + 1) -[i+1] ⊢ motive m n (subNatNat m n) ** unfold subNatNat ** m n : Nat motive : Nat → Nat → Int → Prop hp : ∀ (i n : Nat), motive (n + i) n ↑i hn : ∀ (i m : Nat), motive m (m + i + 1) -[i+1] ⊢ motive m n (match n - m with | 0 => ofNat (m - n) | succ k => -[k+1]) ** match h : n - m with | 0 => have ⟨k, h⟩ := Nat.le.dest (Nat.le_of_sub_eq_zero h) rw [h.symm, Nat.add_sub_cancel_left]; apply hp | succ k => rw [Nat.sub_eq_iff_eq_add (Nat.le_of_lt (Nat.lt_of_sub_eq_succ h))] at h rw [h, Nat.add_comm]; apply hn ** m n : Nat motive : Nat → Nat → Int → Prop hp : ∀ (i n : Nat), motive (n + i) n ↑i hn : ∀ (i m : Nat), motive m (m + i + 1) -[i+1] h : n - m = 0 ⊢ motive m n (match 0 with | 0 => ofNat (m - n) | succ k => -[k+1]) ** have ⟨k, h⟩ := Nat.le.dest (Nat.le_of_sub_eq_zero h) ** m n : Nat motive : Nat → Nat → Int → Prop hp : ∀ (i n : Nat), motive (n + i) n ↑i hn : ∀ (i m : Nat), motive m (m + i + 1) -[i+1] h✝ : n - m = 0 k : Nat h : n + k = m ⊢ motive m n (match 0 with | 0 => ofNat (m - n) | succ k => -[k+1]) ** rw [h.symm, Nat.add_sub_cancel_left] ** m n : Nat motive : Nat → Nat → Int → Prop hp : ∀ (i n : Nat), motive (n + i) n ↑i hn : ∀ (i m : Nat), motive m (m + i + 1) -[i+1] h✝ : n - m = 0 k : Nat h : n + k = m ⊢ motive (n + k) n (match 0 with | 0 => ofNat k | succ k => -[k+1]) ** apply hp ** m n : Nat motive : Nat → Nat → Int → Prop hp : ∀ (i n : Nat), motive (n + i) n ↑i hn : ∀ (i m : Nat), motive m (m + i + 1) -[i+1] k : Nat h : n - m = succ k ⊢ motive m n (match succ k with | 0 => ofNat (m - n) | succ k => -[k+1]) ** rw [Nat.sub_eq_iff_eq_add (Nat.le_of_lt (Nat.lt_of_sub_eq_succ h))] at h ** m n : Nat motive : Nat → Nat → Int → Prop hp : ∀ (i n : Nat), motive (n + i) n ↑i hn : ∀ (i m : Nat), motive m (m + i + 1) -[i+1] k : Nat h : n = succ k + m ⊢ motive m n (match succ k with | 0 => ofNat (m - n) | succ k => -[k+1]) ** rw [h, Nat.add_comm] ** m n : Nat motive : Nat → Nat → Int → Prop hp : ∀ (i n : Nat), motive (n + i) n ↑i hn : ∀ (i m : Nat), motive m (m + i + 1) -[i+1] k : Nat h : n = succ k + m ⊢ motive m (m + succ k) (match succ k with | 0 => ofNat (m - (m + succ k)) | succ k => -[k+1]) ** apply hn ** Qed
Int.subNatNat_add_left ** m n : Nat ⊢ subNatNat (m + n) m = ↑n ** unfold subNatNat ** m n : Nat ⊢ (match m - (m + n) with | 0 => ofNat (m + n - m) | succ k => -[k+1]) = ↑n ** rw [Nat.sub_eq_zero_of_le (Nat.le_add_right ..), Nat.add_sub_cancel_left, ofNat_eq_coe] ** Qed
Int.subNatNat_add_right ** m n : Nat ⊢ subNatNat m (m + n + 1) = -[n+1] ** simp [subNatNat, Nat.add_assoc, Nat.add_sub_cancel_left] ** Qed
Int.natAbs_pos ** a : Int ⊢ 0 < natAbs a ↔ a ≠ 0 ** rw [Nat.pos_iff_ne_zero, Ne, natAbs_eq_zero] ** Qed
Int.natAbs_negOfNat ** n : Nat ⊢ natAbs (negOfNat n) = n ** cases n <;> rfl ** Qed
Int.natAbs_mul_natAbs_eq ** a b : Int c : Nat h : a * b = ↑c ⊢ natAbs a * natAbs b = c ** rw [← natAbs_mul, h, natAbs] ** Qed
Int.natAbs_mul_self' ** a : Int ⊢ ↑(natAbs a) * ↑(natAbs a) = a * a ** rw [← Int.ofNat_mul, natAbs_mul_self] ** Qed
Int.natAbs_eq_natAbs_iff ** a b : Int ⊢ natAbs a = natAbs b ↔ a = b ∨ a = -b ** constructor <;> intro h ** case mp a b : Int h : natAbs a = natAbs b ⊢ a = b ∨ a = -b ** cases Int.natAbs_eq a with | inl h₁ | inr h₁ => cases Int.natAbs_eq b with | inl h₂ | inr h₂ => rw [h₁, h₂]; simp [h] ** case mp.inr a b : Int h : natAbs a = natAbs b h₁ : a = -↑(natAbs a) ⊢ a = b ∨ a = -b ** cases Int.natAbs_eq b with | inl h₂ | inr h₂ => rw [h₁, h₂]; simp [h] ** case mp.inr.inr a b : Int h : natAbs a = natAbs b h₁ : a = -↑(natAbs a) h₂ : b = -↑(natAbs b) ⊢ a = b ∨ a = -b ** rw [h₁, h₂] ** case mp.inr.inr a b : Int h : natAbs a = natAbs b h₁ : a = -↑(natAbs a) h₂ : b = -↑(natAbs b) ⊢ -↑(natAbs a) = -↑(natAbs b) ∨ -↑(natAbs a) = - -↑(natAbs b) ** simp [h] ** case mpr a b : Int h : a = b ∨ a = -b ⊢ natAbs a = natAbs b ** cases h with (subst a; try rfl) | inr h => rw [Int.natAbs_neg] ** case mpr.inl a b : Int h✝ : a = b ⊢ natAbs a = natAbs b ** subst a ** case mpr.inl b : Int ⊢ natAbs b = natAbs b ** try rfl ** case mpr.inl b : Int ⊢ natAbs b = natAbs b ** rfl ** case mpr.inr b : Int ⊢ natAbs (-b) = natAbs b ** rw [Int.natAbs_neg] ** Qed
Int.natAbs_eq_iff ** a : Int n : Nat ⊢ natAbs a = n ↔ a = ↑n ∨ a = -↑n ** rw [← Int.natAbs_eq_natAbs_iff, Int.natAbs_ofNat] ** Qed
Int.sign_neg ** z : Int ⊢ sign (-z) = -sign z ** match z with | 0 | succ _ | -[_+1] => rfl ** z : Int a✝ : Nat ⊢ sign (- -[a✝+1]) = -sign -[a✝+1] ** rfl ** Qed
Int.add_comm ** n m : Nat ⊢ ofNat n + ofNat m = ofNat m + ofNat n ** simp [Nat.add_comm] ** a✝¹ a✝ : Nat ⊢ -[a✝¹+1] + -[a✝+1] = -[a✝+1] + -[a✝¹+1] ** simp [Nat.add_comm] ** Qed
Int.ofNat_add_negSucc_of_lt ** m n : Nat h : m < succ n ⊢ subNatNat m (succ n) = -[n - m+1] ** simp [succ_sub (le_of_lt_succ h), subNatNat] ** Qed
Int.subNatNat_sub ** n m : Nat h : n ≤ m k : Nat ⊢ subNatNat (m - n) k = subNatNat m (k + n) ** rwa [← subNatNat_add_add _ _ n, Nat.sub_add_cancel] ** Qed
Int.subNatNat_add ** m n k : Nat ⊢ subNatNat (m + n) k = ↑m + subNatNat n k ** cases n.lt_or_ge k with | inl h' => simp [subNatNat_of_lt h', succ_pred_eq_of_pos (Nat.sub_pos_of_lt h')] conv => lhs; rw [← Nat.sub_add_cancel (Nat.le_of_lt h')] apply subNatNat_add_add | inr h' => simp [subNatNat_of_le h', subNatNat_of_le (Nat.le_trans h' (le_add_left ..)), Nat.add_sub_assoc h'] ** case inl m n k : Nat h' : n < k ⊢ subNatNat (m + n) k = ↑m + subNatNat n k ** simp [subNatNat_of_lt h', succ_pred_eq_of_pos (Nat.sub_pos_of_lt h')] ** case inl m n k : Nat h' : n < k ⊢ subNatNat (m + n) k = subNatNat m (k - n) ** conv => lhs; rw [← Nat.sub_add_cancel (Nat.le_of_lt h')] ** case inl m n k : Nat h' : n < k ⊢ subNatNat (m + n) (k - n + n) = subNatNat m (k - n) ** apply subNatNat_add_add ** case inr m n k : Nat h' : n ≥ k ⊢ subNatNat (m + n) k = ↑m + subNatNat n k ** simp [subNatNat_of_le h', subNatNat_of_le (Nat.le_trans h' (le_add_left ..)), Nat.add_sub_assoc h'] ** Qed
Int.add_left_comm ** a b c : Int ⊢ a + (b + c) = b + (a + c) ** rw [← Int.add_assoc, Int.add_comm a, Int.add_assoc] ** Qed
Int.add_right_comm ** a b c : Int ⊢ a + b + c = a + c + b ** rw [Int.add_assoc, Int.add_comm b, ← Int.add_assoc] ** Qed
Int.subNatNat_self ** m : Nat ⊢ subNatNat (succ m) (succ m) = 0 ** rw [subNatNat_of_sub_eq_zero (Nat.sub_self ..), Nat.sub_self, ofNat_zero] ** Qed
Int.add_left_neg ** m : Nat ⊢ -↑(succ m) + ↑(succ m) = 0 ** simp ** m : Nat ⊢ - -[m+1] + -[m+1] = 0 ** simp ** Qed
Int.add_right_neg ** a : Int ⊢ a + -a = 0 ** rw [Int.add_comm, Int.add_left_neg] ** Qed
Int.neg_eq_of_add_eq_zero ** a b : Int h : a + b = 0 ⊢ -a = b ** rw [← Int.add_zero (-a), ← h, ← Int.add_assoc, Int.add_left_neg, Int.zero_add] ** Qed
Int.eq_neg_of_eq_neg ** a b : Int h : a = -b ⊢ b = -a ** rw [h, Int.neg_neg] ** Qed
Int.neg_eq_comm ** a b : Int ⊢ -a = b ↔ -b = a ** rw [eq_comm, Int.eq_neg_comm, eq_comm] ** Qed
Int.neg_add_cancel_left ** a b : Int ⊢ -a + (a + b) = b ** rw [← Int.add_assoc, Int.add_left_neg, Int.zero_add] ** Qed
Int.add_neg_cancel_left ** a b : Int ⊢ a + (-a + b) = b ** rw [← Int.add_assoc, Int.add_right_neg, Int.zero_add] ** Qed
Int.add_neg_cancel_right ** a b : Int ⊢ a + b + -b = a ** rw [Int.add_assoc, Int.add_right_neg, Int.add_zero] ** Qed
Int.neg_add_cancel_right ** a b : Int ⊢ a + -b + b = a ** rw [Int.add_assoc, Int.add_left_neg, Int.add_zero] ** Qed
Int.add_left_cancel ** a b c : Int h : a + b = a + c ⊢ b = c ** have h₁ : -a + (a + b) = -a + (a + c) := by rw [h] ** a b c : Int h : a + b = a + c h₁ : -a + (a + b) = -a + (a + c) ⊢ b = c ** simp [← Int.add_assoc, Int.add_left_neg, Int.zero_add] at h₁ ** a b c : Int h : a + b = a + c h₁ : b = c ⊢ b = c ** exact h₁ ** a b c : Int h : a + b = a + c ⊢ -a + (a + b) = -a + (a + c) ** rw [h] ** Qed
Int.neg_add ** a b : Int ⊢ -(a + b) = -a + -b ** apply Int.add_left_cancel (a := a + b) ** a b : Int ⊢ a + b + -(a + b) = a + b + (-a + -b) ** rw [Int.add_right_neg, Int.add_comm a, ← Int.add_assoc, Int.add_assoc b, Int.add_right_neg, Int.add_zero, Int.add_right_neg] ** Qed
Int.sub_self ** a : Int ⊢ a - a = 0 ** rw [Int.sub_eq_add_neg, Int.add_right_neg] ** Qed
Int.sub_zero ** a : Int ⊢ a - 0 = a ** simp [Int.sub_eq_add_neg] ** Qed
Int.zero_sub ** a : Int ⊢ 0 - a = -a ** simp [Int.sub_eq_add_neg] ** Qed
Int.sub_eq_zero_of_eq ** a b : Int h : a = b ⊢ a - b = 0 ** rw [h, Int.sub_self] ** Qed
Int.eq_of_sub_eq_zero ** a b : Int h : a - b = 0 ⊢ a = b ** have : 0 + b = b := by rw [Int.zero_add] ** a b : Int h : a - b = 0 this : 0 + b = b ⊢ a = b ** have : a - b + b = b := by rwa [h] ** a b : Int h : a - b = 0 this✝ : 0 + b = b this : a - b + b = b ⊢ a = b ** rwa [Int.sub_eq_add_neg, Int.neg_add_cancel_right] at this ** a b : Int h : a - b = 0 ⊢ 0 + b = b ** rw [Int.zero_add] ** a b : Int h : a - b = 0 this : 0 + b = b ⊢ a - b + b = b ** rwa [h] ** Qed
Int.sub_sub ** a b c : Int ⊢ a - b - c = a - (b + c) ** simp [Int.sub_eq_add_neg, Int.add_assoc] ** Qed
Int.neg_sub ** a b : Int ⊢ -(a - b) = b - a ** simp [Int.sub_eq_add_neg, Int.add_comm] ** Qed
Int.sub_sub_self ** a b : Int ⊢ a - (a - b) = b ** simp [Int.sub_eq_add_neg, ← Int.add_assoc] ** Qed
Int.sub_neg ** a b : Int ⊢ a - -b = a + b ** simp [Int.sub_eq_add_neg] ** Qed
Int.mul_comm ** a b : Int ⊢ a * b = b * a ** cases a <;> cases b <;> simp [Nat.mul_comm] ** Qed
Int.ofNat_mul_negOfNat ** m n : Nat ⊢ ↑m * negOfNat n = negOfNat (m * n) ** cases n <;> rfl ** Qed
Int.negSucc_mul_negOfNat ** m n : Nat ⊢ -[m+1] * negOfNat n = ofNat (succ m * n) ** cases n <;> rfl ** Qed
Int.mul_assoc ** a b c : Int ⊢ a * b * c = a * (b * c) ** cases a <;> cases b <;> cases c <;> simp [Nat.mul_assoc] ** Qed
Int.mul_left_comm ** a b c : Int ⊢ a * (b * c) = b * (a * c) ** rw [← Int.mul_assoc, ← Int.mul_assoc, Int.mul_comm a] ** Qed
Int.mul_right_comm ** a b c : Int ⊢ a * b * c = a * c * b ** rw [Int.mul_assoc, Int.mul_assoc, Int.mul_comm b] ** Qed
Int.mul_zero ** a : Int ⊢ a * 0 = 0 ** cases a <;> rfl ** Qed
Int.negOfNat_eq_subNatNat_zero ** n : Nat ⊢ negOfNat n = subNatNat 0 n ** cases n <;> rfl ** Qed
Int.ofNat_mul_subNatNat ** m n k : Nat ⊢ ↑m * subNatNat n k = subNatNat (m * n) (m * k) ** cases m with | zero => simp [ofNat_zero, Int.zero_mul, Nat.zero_mul] | succ m => cases n.lt_or_ge k with | inl h => have h' : succ m * n < succ m * k := Nat.mul_lt_mul_of_pos_left h (Nat.succ_pos m) simp [subNatNat_of_lt h, subNatNat_of_lt h'] rw [succ_pred_eq_of_pos (Nat.sub_pos_of_lt h), ← neg_ofNat_succ, Nat.mul_sub_left_distrib, ← succ_pred_eq_of_pos (Nat.sub_pos_of_lt h')]; rfl | inr h => have h' : succ m * k ≤ succ m * n := Nat.mul_le_mul_left _ h simp [subNatNat_of_le h, subNatNat_of_le h', Nat.mul_sub_left_distrib] ** case zero n k : Nat ⊢ ↑zero * subNatNat n k = subNatNat (zero * n) (zero * k) ** simp [ofNat_zero, Int.zero_mul, Nat.zero_mul] ** case succ n k m : Nat ⊢ ↑(succ m) * subNatNat n k = subNatNat (succ m * n) (succ m * k) ** cases n.lt_or_ge k with | inl h => have h' : succ m * n < succ m * k := Nat.mul_lt_mul_of_pos_left h (Nat.succ_pos m) simp [subNatNat_of_lt h, subNatNat_of_lt h'] rw [succ_pred_eq_of_pos (Nat.sub_pos_of_lt h), ← neg_ofNat_succ, Nat.mul_sub_left_distrib, ← succ_pred_eq_of_pos (Nat.sub_pos_of_lt h')]; rfl | inr h => have h' : succ m * k ≤ succ m * n := Nat.mul_le_mul_left _ h simp [subNatNat_of_le h, subNatNat_of_le h', Nat.mul_sub_left_distrib] ** case succ.inl n k m : Nat h : n < k ⊢ ↑(succ m) * subNatNat n k = subNatNat (succ m * n) (succ m * k) ** have h' : succ m * n < succ m * k := Nat.mul_lt_mul_of_pos_left h (Nat.succ_pos m) ** case succ.inl n k m : Nat h : n < k h' : succ m * n < succ m * k ⊢ ↑(succ m) * subNatNat n k = subNatNat (succ m * n) (succ m * k) ** simp [subNatNat_of_lt h, subNatNat_of_lt h'] ** case succ.inl n k m : Nat h : n < k h' : succ m * n < succ m * k ⊢ negOfNat (succ m * succ (pred (k - n))) = -[pred (succ m * k - succ m * n)+1] ** rw [succ_pred_eq_of_pos (Nat.sub_pos_of_lt h), ← neg_ofNat_succ, Nat.mul_sub_left_distrib, ← succ_pred_eq_of_pos (Nat.sub_pos_of_lt h')] ** case succ.inl n k m : Nat h : n < k h' : succ m * n < succ m * k ⊢ negOfNat (succ (pred (succ m * k - succ m * n))) = -↑(succ (pred (succ (pred (succ m * k - succ m * n))))) ** rfl ** case succ.inr n k m : Nat h : n ≥ k ⊢ ↑(succ m) * subNatNat n k = subNatNat (succ m * n) (succ m * k) ** have h' : succ m * k ≤ succ m * n := Nat.mul_le_mul_left _ h ** case succ.inr n k m : Nat h : n ≥ k h' : succ m * k ≤ succ m * n ⊢ ↑(succ m) * subNatNat n k = subNatNat (succ m * n) (succ m * k) ** simp [subNatNat_of_le h, subNatNat_of_le h', Nat.mul_sub_left_distrib] ** Qed
Int.negOfNat_add ** m n : Nat ⊢ negOfNat m + negOfNat n = negOfNat (m + n) ** cases m <;> cases n <;> simp [Nat.succ_add] <;> rfl ** Qed
Int.negSucc_mul_subNatNat ** m n k : Nat ⊢ -[m+1] * subNatNat n k = subNatNat (succ m * k) (succ m * n) ** cases n.lt_or_ge k with | inl h => have h' : succ m * n < succ m * k := Nat.mul_lt_mul_of_pos_left h (Nat.succ_pos m) rw [subNatNat_of_lt h, subNatNat_of_le (Nat.le_of_lt h')] simp [succ_pred_eq_of_pos (Nat.sub_pos_of_lt h), Nat.mul_sub_left_distrib] | inr h => cases Nat.lt_or_ge k n with | inl h' => have h₁ : succ m * n > succ m * k := Nat.mul_lt_mul_of_pos_left h' (Nat.succ_pos m) rw [subNatNat_of_le h, subNatNat_of_lt h₁, negSucc_mul_ofNat, Nat.mul_sub_left_distrib, ← succ_pred_eq_of_pos (Nat.sub_pos_of_lt h₁)]; rfl | inr h' => rw [Nat.le_antisymm h h', subNatNat_self, subNatNat_self, Int.mul_zero] ** case inl m n k : Nat h : n < k ⊢ -[m+1] * subNatNat n k = subNatNat (succ m * k) (succ m * n) ** have h' : succ m * n < succ m * k := Nat.mul_lt_mul_of_pos_left h (Nat.succ_pos m) ** case inl m n k : Nat h : n < k h' : succ m * n < succ m * k ⊢ -[m+1] * subNatNat n k = subNatNat (succ m * k) (succ m * n) ** rw [subNatNat_of_lt h, subNatNat_of_le (Nat.le_of_lt h')] ** case inl m n k : Nat h : n < k h' : succ m * n < succ m * k ⊢ -[m+1] * -[pred (k - n)+1] = ↑(succ m * k - succ m * n) ** simp [succ_pred_eq_of_pos (Nat.sub_pos_of_lt h), Nat.mul_sub_left_distrib] ** case inr m n k : Nat h : n ≥ k ⊢ -[m+1] * subNatNat n k = subNatNat (succ m * k) (succ m * n) ** cases Nat.lt_or_ge k n with | inl h' => have h₁ : succ m * n > succ m * k := Nat.mul_lt_mul_of_pos_left h' (Nat.succ_pos m) rw [subNatNat_of_le h, subNatNat_of_lt h₁, negSucc_mul_ofNat, Nat.mul_sub_left_distrib, ← succ_pred_eq_of_pos (Nat.sub_pos_of_lt h₁)]; rfl | inr h' => rw [Nat.le_antisymm h h', subNatNat_self, subNatNat_self, Int.mul_zero] ** case inr.inl m n k : Nat h : n ≥ k h' : k < n ⊢ -[m+1] * subNatNat n k = subNatNat (succ m * k) (succ m * n) ** have h₁ : succ m * n > succ m * k := Nat.mul_lt_mul_of_pos_left h' (Nat.succ_pos m) ** case inr.inl m n k : Nat h : n ≥ k h' : k < n h₁ : succ m * n > succ m * k ⊢ -[m+1] * subNatNat n k = subNatNat (succ m * k) (succ m * n) ** rw [subNatNat_of_le h, subNatNat_of_lt h₁, negSucc_mul_ofNat, Nat.mul_sub_left_distrib, ← succ_pred_eq_of_pos (Nat.sub_pos_of_lt h₁)] ** case inr.inl m n k : Nat h : n ≥ k h' : k < n h₁ : succ m * n > succ m * k ⊢ -↑(succ (pred (succ m * n - succ m * k))) = -[pred (succ (pred (succ m * n - succ m * k)))+1] ** rfl ** case inr.inr m n k : Nat h : n ≥ k h' : k ≥ n ⊢ -[m+1] * subNatNat n k = subNatNat (succ m * k) (succ m * n) ** rw [Nat.le_antisymm h h', subNatNat_self, subNatNat_self, Int.mul_zero] ** Qed
Int.mul_add ** m n k : Nat ⊢ ↑m * (↑n + ↑k) = ↑m * ↑n + ↑m * ↑k ** simp [Nat.left_distrib] ** m n k : Nat ⊢ ↑m * (↑n + -[k+1]) = ↑m * ↑n + ↑m * -[k+1] ** simp [negOfNat_eq_subNatNat_zero] ** m n k : Nat ⊢ subNatNat (m * n) (m * succ k) = ↑(m * n) + subNatNat 0 (m * succ k) ** rw [← subNatNat_add] ** m n k : Nat ⊢ subNatNat (m * n) (m * succ k) = subNatNat (m * n + 0) (m * succ k) ** rfl ** m n k : Nat ⊢ ↑m * (-[n+1] + ↑k) = ↑m * -[n+1] + ↑m * ↑k ** simp [negOfNat_eq_subNatNat_zero] ** m n k : Nat ⊢ subNatNat (m * k) (m * succ n) = subNatNat 0 (m * succ n) + ↑(m * k) ** rw [Int.add_comm, ← subNatNat_add] ** m n k : Nat ⊢ subNatNat (m * k) (m * succ n) = subNatNat (m * k + 0) (m * succ n) ** rfl ** m n k : Nat ⊢ ↑m * (-[n+1] + -[k+1]) = ↑m * -[n+1] + ↑m * -[k+1] ** simp ** m n k : Nat ⊢ negOfNat (m * succ (succ (n + k))) = negOfNat (m * succ n + m * succ k) ** rw [← Nat.left_distrib, succ_add] ** m n k : Nat ⊢ negOfNat (m * succ (succ (n + k))) = negOfNat (m * succ (n + succ k)) ** rfl ** m n k : Nat ⊢ -[m+1] * (↑n + ↑k) = -[m+1] * ↑n + -[m+1] * ↑k ** simp [Nat.mul_comm] ** m n k : Nat ⊢ negOfNat ((n + k) * succ m) = negOfNat (n * succ m + k * succ m) ** rw [← Nat.right_distrib, Nat.mul_comm] ** m n k : Nat ⊢ -[m+1] * (↑n + -[k+1]) = -[m+1] * ↑n + -[m+1] * -[k+1] ** simp [negOfNat_eq_subNatNat_zero] ** m n k : Nat ⊢ subNatNat (succ m * succ k) (succ m * n) = subNatNat 0 (succ m * n) + ↑(succ m * succ k) ** rw [Int.add_comm, ← subNatNat_add] ** m n k : Nat ⊢ subNatNat (succ m * succ k) (succ m * n) = subNatNat (succ m * succ k + 0) (succ m * n) ** rfl ** m n k : Nat ⊢ -[m+1] * (-[n+1] + ↑k) = -[m+1] * -[n+1] + -[m+1] * ↑k ** simp [negOfNat_eq_subNatNat_zero] ** m n k : Nat ⊢ subNatNat (succ m * succ n) (succ m * k) = ↑(succ m * succ n) + subNatNat 0 (succ m * k) ** rw [← subNatNat_add] ** m n k : Nat ⊢ subNatNat (succ m * succ n) (succ m * k) = subNatNat (succ m * succ n + 0) (succ m * k) ** rfl ** m n k : Nat ⊢ -[m+1] * (-[n+1] + -[k+1]) = -[m+1] * -[n+1] + -[m+1] * -[k+1] ** simp ** m n k : Nat ⊢ ↑(succ m * succ (succ (n + k))) = ↑(succ m * succ n + succ m * succ k) ** rw [← Nat.left_distrib, succ_add] ** m n k : Nat ⊢ ↑(succ m * succ (succ (n + k))) = ↑(succ m * succ (n + succ k)) ** rfl ** Qed
Int.add_mul ** a b c : Int ⊢ (a + b) * c = a * c + b * c ** simp [Int.mul_comm, Int.mul_add] ** Qed
Int.neg_mul_eq_neg_mul ** a b : Int ⊢ a * b + -a * b = 0 ** rw [← Int.add_mul, Int.add_right_neg, Int.zero_mul] ** Qed
Int.neg_mul_eq_mul_neg ** a b : Int ⊢ a * b + a * -b = 0 ** rw [← Int.mul_add, Int.add_right_neg, Int.mul_zero] ** Qed
Int.neg_mul_neg ** a b : Int ⊢ -a * -b = a * b ** simp ** Qed
Int.neg_mul_comm ** a b : Int ⊢ -a * b = a * -b ** simp ** Qed
Int.mul_sub ** a b c : Int ⊢ a * (b - c) = a * b - a * c ** simp [Int.sub_eq_add_neg, Int.mul_add] ** Qed
Int.sub_mul ** a b c : Int ⊢ (a - b) * c = a * c - b * c ** simp [Int.sub_eq_add_neg, Int.add_mul] ** Qed
Int.add_sub_assoc ** a b c : Int ⊢ a + b - c = a + (b - c) ** rw [Int.sub_eq_add_neg, Int.add_assoc, ← Int.sub_eq_add_neg] ** Qed
Int.ofNat_sub ** m n : Nat h : m ≤ n ⊢ ↑(n - m) = ↑n - ↑m ** match m with | 0 => rfl | succ m => show ofNat (n - succ m) = subNatNat n (succ m) rw [subNatNat, Nat.sub_eq_zero_of_le h] ** m n : Nat h : 0 ≤ n ⊢ ↑(n - 0) = ↑n - ↑0 ** rfl ** m✝ n m : Nat h : succ m ≤ n ⊢ ↑(n - succ m) = ↑n - ↑(succ m) ** show ofNat (n - succ m) = subNatNat n (succ m) ** m✝ n m : Nat h : succ m ≤ n ⊢ ofNat (n - succ m) = subNatNat n (succ m) ** rw [subNatNat, Nat.sub_eq_zero_of_le h] ** Qed
Int.negSucc_coe' ** n : Nat ⊢ -[n+1] = -↑n - 1 ** rw [Int.sub_eq_add_neg, ← Int.neg_add] ** n : Nat ⊢ -[n+1] = -(↑n + 1) ** rfl ** Qed
Int.subNatNat_eq_coe ** m n : Nat ⊢ subNatNat m n = ↑m - ↑n ** apply subNatNat_elim m n fun m n i => i = m - n ** case hp m n : Nat ⊢ ∀ (i n : Nat), ↑i = ↑(n + i) - ↑n ** intros i n ** case hp m n✝ i n : Nat ⊢ ↑i = ↑(n + i) - ↑n ** rw [Int.ofNat_add, Int.sub_eq_add_neg, Int.add_assoc, Int.add_left_comm, Int.add_right_neg, Int.add_zero] ** case hn m n : Nat ⊢ ∀ (i m : Nat), -[i+1] = ↑m - ↑(m + i + 1) ** intros i n ** case hn m n✝ i n : Nat ⊢ -[i+1] = ↑n - ↑(n + i + 1) ** simp only [negSucc_coe, ofNat_add, Int.sub_eq_add_neg, Int.neg_add, ← Int.add_assoc] ** case hn m n✝ i n : Nat ⊢ -↑i + -↑1 = ↑n + -↑n + -↑i + -↑1 ** rw [← @Int.sub_eq_add_neg n, ← ofNat_sub, Nat.sub_self, ofNat_zero, Int.zero_add] ** case hn m n✝ i n : Nat ⊢ n ≤ n ** apply Nat.le_refl ** Qed
Int.toNat_sub ** m n : Nat ⊢ toNat (↑m - ↑n) = m - n ** rw [← Int.subNatNat_eq_coe] ** m n : Nat ⊢ toNat (subNatNat m n) = m - n ** refine subNatNat_elim m n (fun m n i => toNat i = m - n) (fun i n => ?_) (fun i n => ?_) ** case refine_1 m n✝ i n : Nat ⊢ (fun m n i => toNat i = m - n) (n + i) n ↑i ** exact (Nat.add_sub_cancel_left ..).symm ** case refine_2 m n✝ i n : Nat ⊢ (fun m n i => toNat i = m - n) n (n + i + 1) -[i+1] ** dsimp ** case refine_2 m n✝ i n : Nat ⊢ toNat -[i+1] = n - (n + i + 1) ** rw [Nat.add_assoc, Nat.sub_eq_zero_of_le (Nat.le_add_right ..)] ** case refine_2 m n✝ i n : Nat ⊢ toNat -[i+1] = 0 ** rfl ** Qed
Int.one_mul ** n : Nat ⊢ ofNat (1 * n) = ofNat n ** rw [Nat.one_mul] ** n : Nat ⊢ -[1 * n+1] = -[n+1] ** rw [Nat.one_mul] ** Qed
Int.mul_one ** a : Int ⊢ a * 1 = a ** rw [Int.mul_comm, Int.one_mul] ** Qed
Int.mul_neg_one ** a : Int ⊢ a * -1 = -a ** rw [Int.mul_neg, Int.mul_one] ** Qed
Int.neg_eq_neg_one_mul ** n : Nat ⊢ -↑(succ n) = -[1 * n+1] ** rw [Nat.one_mul] ** n : Nat ⊢ -↑(succ n) = -[n+1] ** rfl ** n : Nat ⊢ - -[n+1] = ofNat (succ 0 * succ n) ** rw [Nat.one_mul] ** n : Nat ⊢ - -[n+1] = ofNat (succ n) ** rfl ** Qed
Int.sign_mul ** b : Int ⊢ sign (0 * b) = sign 0 * sign b ** simp [Int.mul_zero, Int.zero_mul] ** Qed
Int.le.intro ** a b : Int n : Nat h : a + ↑n = b ⊢ b - a = ↑n ** rw [← h, Int.add_comm] ** a b : Int n : Nat h : a + ↑n = b ⊢ ↑n + a - a = ↑n ** simp [Int.sub_eq_add_neg, Int.add_assoc] ** Qed