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%I #24 Sep 08 2022 08:45:39
%S 12,15,18,20,21,24,25,27,30,32,33,35,36,39,40,42,45,46,48,50,51,53,54,
%T 55,57,60,63,65,66,67,68,69,70,72,74,75,78,79,80,81,84,85,87,88,90,92,
%U 93,95,96,99,100,101,102,105,108,109,110,111,112,114,115,116
%N Numbers n such that 2*n-15 is not a prime.
%C One more than the associated entry in A153049. - _R. J. Mathar_, Jan 05 2011
%C The terms are the values of 2*h*k + k + h + 8, where h and k are positive integers.- _Vincenzo Librandi_, Jan 19 2013
%H Vincenzo Librandi, <a href="/A153047/b153047.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[12,200], !PrimeQ[2*#-15]&] (* _Vladimir Joseph Stephan Orlovsky_, Feb 09 2012 *)
%o (Magma) [n: n in [10..120] | not IsPrime(2*n - 15)]; // _Vincenzo Librandi_, Oct 11 2012
%Y Cf. A097480, A153043, A153045, A153049, A163657.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Dec 17 2008
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