| author | wneuper <Walther.Neuper@jku.at> |
| Sun, 31 Dec 2023 09:42:27 +0100 | |
| changeset 60787 | 26037efefd61 |
| parent 52107 | f8845fc8f38d |
| permissions | -rw-r--r-- |
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theory Functions imports Main begin |
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|
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fun fib :: "nat \<Rightarrow> nat" |
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where |
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"fib 0 = 1" |
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| "fib (Suc 0) = 1" |
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| "fib (Suc (Suc n)) = fib n + fib (Suc n)" |
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thm fib.simps |
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(*"fib (Suc (Suc n))"*) |
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lemma "fib 0 = 1" |
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by simp |
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lemma "fib (Suc 0) = 1" |
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by simp |
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lemma "fib (Suc (Suc (Suc 0))) = (Suc (Suc (Suc 0)))" |
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by simp |
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(*fun sep :: "’a \<Rightarrow> ’a list \<Rightarrow> ’a list" |
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where |
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"sep a (x#y#xs) = x # a # sep a (y # xs)" |
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| "sep a xs |
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= xs"*) |
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end |