16 lines
244 B
Text
16 lines
244 B
Text
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open nat
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definition nrec [recursor] := @nat.rec
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definition myadd x y :=
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nrec y (λ n r, succ r) x
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theorem myadd_zero : ∀ n, myadd n 0 = n :=
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begin
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intro n, induction n with n ih,
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reflexivity,
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esimp [myadd],
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state,
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rewrite ih
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end
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