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 A071887 #9 Nov 04 2013 13:16:09 %S A071887 37,38,41,54,57,58 %N A071887 Conjectured values of n whose trajectory under map x -> A002487(x)*A002487(x+1) does not go into a cycle. %C A071887 Why isn't 42 in this list? It does not enter a cycle in under 100 iterations which is as far as I could check. [Sean A. Irvine, Oct 05 2011] %Y A071887 Cf. A002487, A070871, A071884, A071885, A071886. %K A071887 nonn,more %O A071887 1,1 %A A071887 _J. H. Conway_, Jun 10 2002