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  • Committer: Stephen Compall
  • Date: 2011-08-08 23:29:25 UTC
  • Revision ID: scompall@nocandysw.com-20110808232925-t72zz3jaadmgddru
recursive pascal number

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sicp-1.scm
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        (if (<= n0 n)
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            (lp n-2 n-1 (+ n-1 (* 2 n-2) (* 3 n-3)) (+ 1 n0))
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            n-1))))
 
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;;; Ex 1.12
 
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(define (pascal x y)
 
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  (if (or (= 0 x) (= 0 y))
 
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      1
 
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      (+ (pascal (max 0 (- x 1)) (max 0 y))
 
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         (pascal (max 0 x) (max 0 (- y 1))))))