Playing with prime numbers with Egison

twin primes

/home/egi/egison3% egison                                                                                                                                                                 [0]
Egison Version 3.0.8 (C) 2011-2013 Satoshi Egi
http://egison.pira.jp
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> (take 10 (match-all primes (list integer) [<join _ <cons $n <cons ,(+ n 2) _>>> [n (+ n 2)]]))
{[3 5] [5 7] [11 13] [17 19] [29 31] [41 43] [59 61] [71 73] [101 103] [107 109]}
> (take 10 (match-all primes (list integer) [<join _ <cons $n <cons ,(+ n 4) _>>> [n (+ n 4)]]))
{[7 11] [13 17] [19 23] [37 41] [43 47] [67 71] [79 83] [97 101] [103 107] [109 113]}
> (take 1 (match-all primes (list integer) [<join _ <cons $n <cons ,(+ n 2) <cons ,(+ n 4) _>>>> [n (+ n 2) (+ n 4)]]))
{[3 5 7]}
> (take 2 (match-all primes (list integer) [<join _ <cons $n <cons ,(+ n 2) <cons ,(+ n 4) _>>>> [n (+ n 2) (+ n 4)]]))
^C
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