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n divisible by at least one twin prime (A001097).
1

%I #18 May 20 2014 09:46:56

%S 3,5,6,7,9,10,11,12,13,14,15,17,18,19,20,21,22,24,25,26,27,28,29,30,

%T 31,33,34,35,36,38,39,40,41,42,43,44,45,48,49,50,51,52,54,55,56,57,58,

%U 59,60,61,62,63,65,66,68,69,70,71,72,73,75,76,77,78,80,81,82,84,85,86,87

%N n divisible by at least one twin prime (A001097).

%C Complement of A062729.

%e 36 is included because 36 is divisible by 3 and 3+2 is a prime.

%o (PARI) isok(n) = {my(f = factor(n)); for (i=1, #f~, p = f[i, 1]; if (isprime(p-2) || isprime(p+2), return (1));); return (0);} \\ _Michel Marcus_, May 20 2014

%K nonn

%O 1,1

%A _Leroy Quet_, Jul 09 2001

%E Offset changed to 1 by _Michel Marcus_, May 20 2014