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 A074931 #16 Oct 13 2013 03:57:48
%S A074931 3,5,17,29,41,71,149,281,317,347,359,397,647,751,787,857,907,1093,
%T A074931 1279,1381,1511,1531,1663,1783,2447,2683,2803,3271,3323,4019,4153,
%U A074931 4513,4567,4639,5557,5647,5801,5923,6599,6659,6911,7013,7573,7883,9187,9257,9431
%N A074931 Primes p such that 3p is equidistant from consecutive prime twin pairs.
%C A074931 Numbers equidistant from consecutive twins (see A074953) are multiples of 3 and they may be almost primes only of form 3*prime. In the sequence, these primes are given. Also: A001748 (3*prime 2-almost-primes) and A001358 (all 2-almost-primes).
%e A074931 17 is in the sequence because 3 * 17 = 51 is equidistant between {41, 43} and {59, 61}.
%e A074931 19 is not in the sequence because 3 * 19 = 57, which is much closer to {59, 61} than to {41, 43}.
%Y A074931 Cf. A001358, A001748, A074953.
%K A074931 nonn
%O A074931 1,1
%A A074931 N. Fernandez (primeness(AT)borve.org), _Zak Seidov_, Oct 10 2002
%E A074931 New name from _Charles R Greathouse IV_, Oct 12 2013