doc-src/Tutorial/Recdef/fib
author wenzelm
Thu, 04 Oct 2001 15:20:40 +0200
changeset 11670 59f79df42d1f
parent 6100 40d66bc3e83f
permissions -rw-r--r--
proof by cases and induction on types and sets (used to be specific for HOL);
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consts fib :: nat => nat
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recdef fib "measure(%n. n)"
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  "fib 0 = 0"
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  "fib 1 = 1"
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  "fib (Suc(Suc x)) = fib x + fib (Suc x)"