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%I #17 Apr 15 2019 14:03:08
%S 2,3,197,241,283,317,359,463,499,521,547,577,617,719,773,787,829,883,
%T 887,937,967,983,1061,1093,1109,1129,1171,1193,1229,1249,1319,1327,
%U 1373,1399,1451,1489,1523,1627,1637,1667,1669,1699,1733,1787,1801,1823,1831,1847
%N Primes p such that p+6, p+12 and p+18 are composite.
%C Subsequence of A233314 and A140555: a(3) = 197 = A233314(7) = A140555(19).
%H Zak Seidov, <a href="/A233318/b233318.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Prime[Range[400]], ! PrimeQ[# + 6] && ! PrimeQ[# + 12] && ! PrimeQ[# + 18] &] (* _T. D. Noe_, Dec 10 2013 *)
%t Select[Prime[Range[400]],AllTrue[#+{6,12,18},CompositeQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Apr 15 2019 *)
%Y Cf. A140555, A233314.
%K nonn
%O 1,1
%A _Zak Seidov_, Dec 07 2013