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 A214897 #9 Jul 16 2015 23:38:23 %S A214897 1,10,11,18,19,56,136 %N A214897 Conway's subprime Fibonacci sequence: cycle lengths. %C A214897 Similar to the Fibonacci recursion starting with a pair of positive integers, but each new nonprime term is divided by its least prime factor. The recursion enters a loop of length a(n) after a finite number of steps. Conjecture: the list of loops is complete (checked to [10^5, 10^5]), loops of length a(n) are unique and no infinite chains exist. %H A214897 Richard K. Guy, Tanya Khovanova and Julian Salazar, <a href="http://arxiv.org/abs/1207.5099">Conway's subprime Fibonacci sequences</a>, arXiv:1207.5099v1 [math.NT] %t A214897 see A214674 %Y A214897 Cf. A000045, A020639, A175723, A214551, A014682, A214674, A214892-A214898. %K A214897 nonn %O A214897 1,2 %A A214897 _Wouter Meeussen_, Jul 29 2012