This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A166563 #13 Sep 08 2022 08:45:48 %S A166563 5,6,10,13,15,17,18,20,25,27,28,30,31,34,35,36,39,40,41,44,45,48,50, %T A166563 52,55,57,59,60,61,62,65,69,70,72,74,75,76,80,82,83,85,86,89,90,93,94, %U A166563 95,96,97,100,103,104,105,109,110,111,112,115,116,118,120,121,122,125,126 %N A166563 Numbers n such that 12*n+5 is not prime. %H A166563 Vincenzo Librandi, <a href="/A166563/b166563.txt">Table of n, a(n) for n = 1..1000</a> %e A166563 Distribution of the terms in the following triangular array: %e A166563 *; %e A166563 *,*; %e A166563 *,*,*; %e A166563 *,*,*,*; %e A166563 *,*,6,*,*; %e A166563 *,5,*,*,*,*; %e A166563 *,*,*,*,*,*,*; %e A166563 *,*,*,*,*,18,*,*; %e A166563 *,*,*,*,17,*,*,*,*; %e A166563 *,*,*,*,*,*,*,*,*,*; %e A166563 *,*,13,*,*,*,*,*,36,*,*; %e A166563 *,10,*,*,*,*,*,35,*,*,*,*; etc. %e A166563 where * marks the non-integer values of (2*h*k + k + h - 2)/6 with h >= k >= 1. - _Vincenzo Librandi_, Jan 14 2013 %t A166563 Select[Range[0, 200], !PrimeQ[12 # + 5] &] (* _Vincenzo Librandi_, Jan 14 2013 *) %o A166563 (Magma) [n: n in [0..150] | not IsPrime(12*n+5)]; // _Vincenzo Librandi_, Jan 14 2013 %Y A166563 Cf. A167055. %K A166563 nonn,easy %O A166563 1,1 %A A166563 _Vincenzo Librandi_, Oct 29 2009