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 A070799 #6 Jun 24 2014 01:08:24
%S A070799 4,9,14,19,20,24,29,31,34,39,42,44,48,49,53,54,59,64,65,69,74,75,79,
%T A070799 82,84,86,88,89,94,97,99,104,108,109,111,114,116,119,124,129,130,133,
%U A070799 134,139,140,141,144,149,150,152,154,157,159,163,164,167,169,174,179,180
%N A070799 Numbers of the form 6jk-j-k.
%C A070799 Equivalently, numbers n such that 6n+1 has a factor == 5 (mod 6).
%C A070799 These numbers, together with numbers of the form 6jk+j+k (A070043) are the numbers n for which 6n+1 is composite (A046954). If we also add in the numbers of the form 6jk+j-k (A046953), we get the numbers n such that 6n-1 and 6n+1 do not form a pair of twin primes (A067611).
%e A070799 31 = 6*2*3 - 2 - 3. Equivalently, 6*31+1 = (6*2-1)*(6*3-1).
%t A070799 Select[Range[250], MemberQ[Mod[Take[Divisors[6#+1], {2, -2}], 6], 5]&]
%Y A070799 Cf. A070043, A046953, A046954, A067611.
%K A070799 nonn
%O A070799 1,1
%A A070799 _Jon Perry_, May 05 2002
%E A070799 Edited by _Dean Hickerson_, May 07 2002