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 A088861 #8 Aug 03 2021 18:48:39 %S A088861 1,2,3,2,5,6,5,8,9,8,9,10,9,14,15,16,13,14,17,20,21,20,21,22,21,22,23, %T A088861 24,29,30,31,28,29,32,35,36,37,34,35,38,39,40,39,40,41,42,41,42,47,50, %U A088861 51,50,53,54,53,54,55,56,57,58,59,50,51,62,63,64,63,68,69,70,71,72,65 %N A088861 Third column of triangle in A088643. %Y A088861 Cf. A088643. A088631 gives second column. %K A088861 nonn,easy %O A088861 1,2 %A A088861 _N. J. A. Sloane_, Nov 26 2003 %E A088861 More terms from _John W. Layman_, Dec 04 2003