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 A118878 #6 May 26 2014 23:48:49 %S A118878 1,190,1,87,1,0,189,0,86,0,0,188,0,85,191,0,0,95,0,190,1,0,184,0,3, %T A118878 187,0,0,91,0,96,0,0,180,88,0,183,0,0,87,1,92,0,0,3,84,0,179,0,0,191, %U A118878 0,88,0,2,190,2,87,2,1,2,97,2,192,3,0,186,0,83,189,0,0,93,0,98,0,0,182,0,1,185,0,0,89,3,94,0,0,178,86,0,181,0,0,193,0,90,0,0,1 %N A118878 Let T(S,Q) be the sequence obtaining by starting with S and repeatedly reversing the digits and adding Q to get the next term. a(n) is the number of steps for T(n,5) to reach a cycle, or -1 if no cycle is ever reached. %C A118878 Is a(n) ever -1? If so then n > 10000. %C A118878 The cycle has length 207 for S <= 1015, but for S = 1016 it has length 36 (see A118879). %H A118878 N. J. A. Sloane and others, <a href="/wiki/Sequences_of_RADD_type">Sequences of RADD type</a>, OEIS wiki. %Y A118878 Cf. A117828, A117800, A118879. %K A118878 nonn,base %O A118878 1,2 %A A118878 _N. J. A. Sloane_, May 26 2006