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 A226630 #7 Jun 15 2013 01:33:22 %S A226630 1,11,17,19,23,25,29,31,49,77,85,95,97,113,115,119,121,131,139,145, %T A226630 179,181,185,193,217,311,313,371,385,407,431,451,467,473,475,485,491, %U A226630 493,503,527,601,605,641,695,697,791,805,847,973,1163,1219,1241,1295,1417 %N A226630 Positive integers k with at least one primitive cycle of positive integers under iteration by the 3x-k function. %C A226630 A cycle is called primitive if its elements are not a common multiple of the elements of another cycle. %C A226630 The 3x-k function T_k is defined by T_k(x) = x/2 if x is even, (3x-k)/2 if x is odd. GCD(k,6)=1. %H A226630 Geoffrey H. Morley, <a href="/A226630/b226630.txt">Table of n, a(n) for n = 1..600</a> %Y A226630 Cf. A226633. %K A226630 nonn %O A226630 1,2 %A A226630 _Geoffrey H. Morley_, Jun 13 2013