15 lines
369 B
Text
15 lines
369 B
Text
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inductive list (A : Type) :=
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| nil : list A
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| cons : A → list A → list A
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open nat prod
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example (A B : Type) (d c : nat) (h₀ : c = 0) (a : A) (b : list B) (h₁ : A = list B) (h₂ : eq.rec_on h₁ a = @list.nil B) (h₃ : d = c) (h₄ : d + 1 = d + 2)
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: b = eq.rec_on h₁ a × c = 1:=
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begin
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substvars,
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state,
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injection h₄,
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contradiction
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end
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