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 A068633 #8 Dec 05 2013 19:55:11 %S A068633 11,21,31,22,51,2131,71,23,32,2151,111,2231,131,2171,3151,24,171,2132, %T A068633 191,2251,3171,21111,231,2331,52,21131,33,2271,291,213151,311,25, %U A068633 31111,21171,5171,2232,371,21191,31131,2351,411,213171,431,22111 %N A068633 a(1) = 11 by convention; for n > 1, if n = p^a*q^b... then a(n) = concatenate(p,a,q,b,...). %C A068633 Apart from the conventional initial term, a duplicate of A067599. See there for further comments, examples, references and other information. %K A068633 base,easy,nonn %O A068633 1,1 %A A068633 _Amarnath Murthy_, Feb 27 2002 %E A068633 Edited by _M. F. Hasler_, Oct 06 2013