2015-02-06 18:26:06 +00:00
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import data.nat
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2015-10-14 19:27:09 +00:00
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open nat algebra
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2015-02-06 18:26:06 +00:00
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variables (f : nat → nat → nat → nat) (a b c : nat)
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example (H₁ : a = b) (H₂ : f b a b = 0) : f a a a = 0 :=
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2015-03-28 00:26:06 +00:00
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by rewrite [H₁ at -{2}, H₂]
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2015-02-06 18:26:06 +00:00
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example (H₁ : a = b) (H₂ : f b a b = 0) (H₃ : c = f a a a) : c = 0 :=
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2015-03-28 00:26:06 +00:00
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by rewrite [H₁ at H₃ -{2}, H₂ at H₃, H₃]
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