%I #16 Sep 08 2022 08:45:56
%S 2,6,7,8,12,13,15,17,19,20,22,27,28,29,30,32,34,37,41,42,44,46,47,48,
%T 51,52,54,55,57,60,62,63,65,67,68,69,72,73,74,75,76,77,80,81,82,83,84,
%U 85,87,90,91,92,93,96,97,98,102,103,104,105,106,107,111,112,117,118
%N Numbers n such that 24*n+17 is not prime.
%H Vincenzo Librandi, <a href="/A189242/b189242.txt">Table of n, a(n) for n = 1..1000</a>
%e Distribution of the terms in the following triangular array:
%e *;
%e *,*;
%e *,*,*;
%e *,*,*,*;
%e *,*,*,*,*;
%e *,2,*,*,*,*;
%e *,*,*,*,*,*,*;
%e *,*,*,*,*,*,*,*;
%e *,*,*,*,8,*,*,*,*;
%e *,*,*,*,*,*,*,*,*,*;
%e *,*,6,*,*,*,*,*,*,*,*;
%e *,*,*,*,*,*,*,17,*,*,*,*; etc.
%e where * marks the non-integer values of (2*h*k + k + h - 8)/12 with h >= k >= 1. - _Vincenzo Librandi_, Jan 15 2013
%t Select[Range[1,300],!PrimeQ[24 # + 17] &] (* _Vincenzo Librandi_, Aug 05 2012 *)
%o (Magma) [n: n in [0..200] | not IsPrime(24*n+17)]; // _Vincenzo Librandi_, Apr 19 2011
%Y Cf. A139531, A107181.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Apr 19 2011