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 A130575 #3 Mar 30 2012 18:50:58 %S A130575 0,1,2,3,4,5,6,7,8,9,10,11,21,22,31,32,33,41,42,43,44,51,52,53,54,55, %T A130575 61,62,63,64,65,66,71,72,73,74,75,76,77,81,82,83,84,85,86,87,88,101, %U A130575 211,212,310,311,312,313,410,411,412,413,414,510,511,512,513,514,515,610 %N A130575 Fixed points of the permutations A130571, A130572, A130573 and A130574. %C A130575 A130571(a(n))=a(n), A130572(a(n))=a(n), A130573(a(n))=a(n) and A130574(a(n))=a(n). %K A130575 nonn %O A130575 0,3 %A A130575 _Reinhard Zumkeller_, Jun 05 2007