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%I #10 Sep 08 2022 08:45:39
%S 2,3,6,7,9,12,15,16,17,18,20,21,22,23,24,25,27,28,30,32,33,36,37,38,
%T 39,42,44,45,47,48,50,51,52,53,54,56,57,58,60,61,62,63,64,65,66,67,69,
%U 71,72,75,76,77,78,79,81,82,83,84,85,86,87,88,90,92,93,94
%N Numbers n such that 16*n+3 is not prime.
%H Vincenzo Librandi, <a href="/A153348/b153348.txt">Table of n, a(n) for n = 1..1000</a>
%e Triangle begins:
%e *;
%e *,*;
%e *,2,*;
%e *,*,*,*;
%e *,*,*,6,*;
%e *,*.*,*,*,*;
%e *,*,*,*,*,12,*;
%e 3,*,*,*,*,*,*,*;
%e *,*,*,*,*,*,*,20,*;
%e *,*,9,*,*,*,*,*,*,*;
%e *,7,*,*,*,*,*,*,*,30,*;
%e *,*,*,*,17,*,*,*,*,*,*,*;
%e where * marks the non-integer values of (2*h*k + k + h - 1)/8 with h >= k >= 1.
%t Select[Range[200], !PrimeQ[16*# + 3]&] (* _Vincenzo Librandi_, Jan 13 2013 *)
%o (Magma) [n: n in [0..150] | not IsPrime(16*n + 3)]; // _Vincenzo Librandi_, Jan 13 2013
%Y Cf. A092022.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Dec 24 2008
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