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 A160801 #9 Feb 24 2021 02:48:18 %S A160801 1,2,4,2,1,2,3,1,1,2,3,3,3,5,5,2,1,2,3,2,2,4,6,5,3,5,5,2,2,4,6,1,2,3, %T A160801 2,2,4,6,5,3,5,5,2,2,4,6,5,4,7,8,6,8,14,17,13,10,9,8,3,3,4,5,6,7,8,7, %U A160801 6,8,11,14,17,19,10 %N A160801 First differences of A160800. %C A160801 Number of toothpicks added to the spiral at the n-th stage. %H A160801 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 A160801 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 A160801 Cf. A000045, A139250, A139251, A160426, A160427, A160800. %K A160801 nonn %O A160801 1,2 %A A160801 _Omar E. Pol_, May 26 2009 %E A160801 Terms after a(32) from _Nathaniel Johnston_, Mar 30 2011