16 lines
311 B
Text
16 lines
311 B
Text
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import data.nat
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open nat
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constant f : nat → nat
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definition g (a : nat) := a
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example (a b : nat) : a + 0 = 0 + g b → f (f b) = f (f a) :=
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suppose a + 0 = 0 + g b,
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assert a = b, by unfold g at *; simp,
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by simp
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attribute g [reducible]
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example (a b : nat) : a + 0 = 0 + g b → f (f b) = f (f a) :=
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by simp
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