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 A073142 #5 Mar 30 2012 17:27:38 %S A073142 0,2178,11436678,108811891188,118722683079 %N A073142 List of smallest solutions for some k of x = f^k(x), n <> f^j(n) for j < k, where f: m -> |m - reverse(m)|. %C A073142 In the definition, j can be restricted to proper divisors of k. A073143 gives the corresponding values of k. A073144(n) gives the smallest m such that the 'Reverse and Subtract' trajectory of m leads to a(n). Presumably a(6) = 1186781188132188 with k = 17. %e A073142 a(3) = 11436678 is the smallest solution of x = f^14(x) and there is no k such that x = f^k(x) has a smallest solution between a(2) = 2178 and a(3). %Y A073142 Cf. A072137, A072141, A072142, A072143, A072718, A072719, A073143, A073144. %K A073142 base,more,nonn %O A073142 1,2 %A A073142 _Klaus Brockhaus_, Jul 17 2002 %E A073142 Offset changed by _N. J. A. Sloane_, Dec 01 2007