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%I #10 Sep 08 2022 08:45:39
%S 2,3,5,6,7,8,9,11,12,14,15,16,17,18,20,21,22,23,24,26,27,28,29,30,31,
%T 32,33,34,35,36,37,38,39,41,42,44,45,46,47,48,49,50,51,52,53,54,56,57,
%U 58,59,60,61,62,63,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82
%N Numbers n such that either 2n+3 is not prime or 4n+7 is not prime.
%C Complement of A152843: Numbers n such that both 2n+3 and 4n+7 are prime.
%H Vincenzo Librandi, <a href="/A152854/b152854.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[100],!PrimeQ[2#+3]||!PrimeQ[4#+7]&] (* _Harvey P. Dale_, Jan 18 2012 *)
%o (Magma) [n: n in [0..90] | not IsPrime(2*n+3) or not IsPrime(4*n+7)]; // _Vincenzo Librandi_, Oct 20 2012
%K nonn
%O 1,1
%A _Vincenzo Librandi_, Dec 14 2008
%E Edited and extended by _Klaus Brockhaus_, Dec 23 2008
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