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 A055176 #4 Mar 30 2012 18:57:03 %S A055176 2,1,4,3,5,6,7,8,9,10,12,13,15,16,18,19,21,11,22,24,25,28,31,34,33,36, %T A055176 23,26,20,17,38,29,45,30,14,42,48,32,44,52,35,37,47,56,40,27,51,61,43, %U A055176 57,65,41,39,69,49,74,54,71,76,59,73,79,62 %N A055176 n-th distinct number to appear in A055174; also the n-th to appear in A055190. %C A055176 Conjecture: this sequence is a permutation of the positive integers. %K A055176 nonn %O A055176 1,1 %A A055176 _Clark Kimberling_, Apr 27 2000