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 A220523 #10 Jan 05 2013 02:29:58 %S A220523 0,1,2,4,4,4,4,7,8,4,4,8,12,8,8,13,16,4,4,8,12,16,16,20,24,12,8,16,28, %T A220523 16,16,25,32,4,4,8,12,16,16,22,32,26,20,24,40,32,40,41,48,20,8 %N A220523 Number of toothpicks or D-toothpicks added at n-th stage in the structure of the D-toothpick "narrow" triangle of A220522. %C A220523 Essentially the first differences of A220522. First differs from A194443 at a(47). %H A220523 N. J. A. Sloane, <a href="/wiki/Catalog_of_Toothpick_and_CA_Sequences_in_OEIS">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a> %H A220523 <a href="/index/To#toothpick">Index entries for sequences related to toothpick sequences</a> %e A220523 Written as an irregular triangle begins: %e A220523 0; %e A220523 1; %e A220523 2; %e A220523 4,4; %e A220523 4,4,7,8; %e A220523 4,4,8,12,8,8,13,16; %e A220523 4,4,8,12,16,16,20,24,12,8,16,28,16,16,25,32; %e A220523 4,4,8,12,16,16,22,32,26,20,24,40,32,40,41,48,20,8,... %Y A220523 Cf. A139250, A139251, A194441, A194443, A194445, A220521, A220522. %K A220523 nonn,more %O A220523 0,3 %A A220523 _Omar E. Pol_, Dec 15 2012