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 A151885 #11 Feb 24 2021 02:48:18 %S A151885 0,1,3,5,11,5,15,17,39,5,15,25,55,17,51,61,139,5,15,25,55,25,75,85, %T A151885 195,17,51,85,187,61,183,217,495,5,15,25,55,25,75,85,195,25,75,125, %U A151885 275,85,255,305,695,17,51,85,187,85,255,289,663 %N A151885 Similar to the original toothpick sequence A139250, except that the rule is now: a toothpick changes state if its midpoint is adjacent to exactly one ON toothpick. %C A151885 In the original toothpick sequence A139250, a toothpick simply turned ON (and stayed ON) if its midpoint was adjacent to exactly one ON toothpick. %C A151885 Related to A139250 in the same way that A079315 is related to A147562. %H A151885 Nathaniel Johnston, <a href="/A151885/b151885.txt">Table of n, a(n) for n = 0..925</a> %H A151885 David Applegate, Omar E. Pol and N. J. A. Sloane, <a href="/A000695/a000695_1.pdf">The Toothpick Sequence and Other Sequences from Cellular Automata</a>, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.] %H A151885 Nathaniel Johnston, <a href="/A151885/a151885.c.txt">C program for computing terms of A151885-A151888</a> %H A151885 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 A151885 N. J. A. Sloane, <a href="/A151885/a151885.pdf">Illustration of first 8 generations</a> %F A151885 a(n) = a(n-1) + A151888(n). %Y A151885 Cf. A151886-A151888, A139250, A139251, A147562, A079314, A079315. %K A151885 nonn %O A151885 0,3 %A A151885 _N. J. A. Sloane_, Jul 23 2009 %E A151885 Terms after a(8) from _Nathaniel Johnston_, Apr 02 2011