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 A073143 #6 Mar 30 2012 17:27:38 %S A073143 1,2,14,22,12 %N A073143 Numbers k such that A073142(n) = f^k(A073142(n)), where f: m -> |m - reverse(m)|. %C A073143 Presumably a(6) = 17. a(n) is the length of the periodic part (cf. A072137) of the trajectory of A073142(n). Question: Does every k > 0 appear in this sequence? %e A073143 a(3) = 14 since A073142(2) = 11436678 is the smallest solution of x = f^14(x). %Y A073143 Cf. A072137, A072141, A072142, A072143, A072718, A072719, A073142, A073144. %K A073143 base,more,nonn %O A073143 1,2 %A A073143 _Klaus Brockhaus_, Jul 17 2002 %E A073143 Offset changed by _N. J. A. Sloane_, Dec 01 2007