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 A153167 #10 Apr 15 2015 16:52:03 %S A153167 2,4,6,7,8,10,12,13,14,16,18,19,20,22,23,24,25,26,28,30,31,32,33,34, %T A153167 36,37,38,40,41,42,43,44,46,47,48,49,50,52,53,54,55,56,58,59,60,61,62, %U A153167 63,64,66,67,68,70,71,72,73,74,75,76,77,78,79,80,82,83,84,85,86,88,89,90 %N A153167 Numbers n such that n+2 is not a Chen prime. %C A153167 Contains all strictly positive even numbers A005843. %C A153167 For each odd k>1 we can accumulate the numbers == k^2-2 (mod 2k) in a row, the last entry equal to A073577(k): %C A153167 7; (k=3) %C A153167 13, 23; (k=5) %C A153167 19, 33, 47; (k=7) %C A153167 25, 43, 61, 79; (k=9) %C A153167 31, 53, 75, 97, 119; (k=11) %C A153167 7, 63, 89, 115, 141, 167; (k=13) %C A153167 43, 73, 103, 133, 163, 193,223; (k=17) %C A153167 49, 83, 17, 151,185, 219, 253, 287; (k=19) %C A153167 Each element T of this table has the format T= k^2-2-j*2*k, so T+2 is of the form k*(k-2*j), therefore not prime, and consequently all elements T are in the sequence. %Y A153167 Cf. A109611, A040976, A073577, A067076. %K A153167 nonn %O A153167 1,1 %A A153167 _Vincenzo Librandi_, Dec 20 2008 %E A153167 Edited, 41, 59 (see A102540) etc. inserted by _R. J. Mathar_, Oct 16 2009