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 A160171 #11 Feb 24 2021 02:48:18 %S A160171 0,1,4,8,8,24,32,32,56,80,80,88,112,160,168,240,224,344,320,320,344, %T A160171 448,528,536,704,704,872,736,880,840,1024,1088,1256,1328,1392,1416, %U A160171 1440,1504,1656 %N A160171 First differences of X-toothpicks numbers A160170. %C A160171 Number of X-toothpicks added at n-th stage to the three-dimensional X-toothpick structure of A160170. %C A160171 For another version see A170875. %H A160171 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 A160171 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 A160171 <a href="/index/To#toothpick">Index entries for sequences related to toothpick sequences</a> %Y A160171 X-toothpick sequence: A160170. %Y A160171 Cf. A139250, A139251, A160120, A160121, A160160, A160161, A170875. %K A160171 nonn %O A160171 0,3 %A A160171 _Omar E. Pol_, May 03 2009, Dec 13 2010 %E A160171 More terms (a(6)-a(38)) based on Email from _R. J. Mathar_ dated on Jan 10 2010.