author  paulson 
Wed, 13 Oct 1999 12:07:23 +0200  
changeset 7843  077d305615df 
parent 5183  89f162de39cf 
child 8844  db71c334e854 
permissions  rwrr 
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(* Title: HOL/Power.thy 
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ID: $Id$ 
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Author: Lawrence C Paulson, Cambridge University Computer Laboratory 
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Copyright 1997 University of Cambridge 
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The (overloaded) exponentiation operator, ^ :: [nat,nat]=>nat 
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Also binomial coefficents 
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*) 
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Power = Divides + 
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consts 
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binomial :: "[nat,nat] => nat" (infixl "choose" 65) 
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primrec 
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"p ^ 0 = 1" 
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"p ^ (Suc n) = (p::nat) * (p ^ n)" 
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primrec 
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binomial_0 "(0 choose k) = (if k = 0 then 1 else 0)" 
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binomial_Suc "(Suc n choose k) = 
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(if k = 0 then 1 else (n choose (k  1)) + (n choose k))" 
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end 
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25 