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 A161412 #10 Jun 14 2022 14:11:43 %S A161412 0,1,2,3,5,9,12,15,19,25,29,34,39,49,58,63 %N A161412 V-toothpick sequence starting at the corner of an infinite square from which protrudes a half toothpick with an angle = Pi/6. %C A161412 The sequence gives the number of V-toothpicks in the structure after n rounds. A161413 (the first differences) gives the number added at the n-th round. %H A161412 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 A161412 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> %Y A161412 V-toothpick sequence: A161206. %Y A161412 Cf. A139250, A160120, A160406, A161328, A161413. %K A161412 more,nonn %O A161412 0,3 %A A161412 _Omar E. Pol_, Jun 10 2009