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A-M baby

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Ingy döt Net 2013-04-10 21:29:02 -07:00
parent 764da6cbbb
commit db842d013d
19005 changed files with 197040 additions and 7 deletions
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Task/Hofstadter-Q-sequence/Racket/hofstadter-q-sequence.rkt Normal file
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#lang racket
(define t (make-hash))
(hash-set! t 0 0)
(hash-set! t 1 1)
(hash-set! t 2 1)
(define (Q n)
(hash-ref! t n ( () (+ (Q (- n (Q (- n 1))))
(Q (- n (Q (- n 2))))))))
(for/list ([i (in-range 1 11)]) (Q i))
(Q 1000)
;; extra credit
(for/sum ([i 100000]) (if (< (Q (add1 i)) (Q i)) 1 0))