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 A160416 #6 Feb 24 2021 02:48:18 %S A160416 0,1,8,11,32,39,80,89,146,159 %N A160416 Number of "ON" cells at n-th stage in simple 2-dimensional cellular automaton (see Comments for precise definition). %H A160416 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 A160416 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> %e A160416 If we label the generations of cells turned ON by consecutive numbers we get the cell pattern shown below: %e A160416 ..9...9...9...9...9 %e A160416 ...888.888.888.888. %e A160416 ...878.878.878.878. %e A160416 ...886668666866688. %e A160416 ..9..656.656.656..9 %e A160416 ...886644464446688. %e A160416 ...878.434.434.878. %e A160416 ...886644222446688. %e A160416 ..9..656.212.656..9 %e A160416 000000000022446688. %e A160416 0000000000.434.878. %e A160416 000000000064446688. %e A160416 000000000056.656..9 %e A160416 000000000066866688. %e A160416 0000000000.878.878. %e A160416 0000000000.888.888. %e A160416 00000000009...9...9 %e A160416 0000000000......... %e A160416 0000000000......... %Y A160416 Cf. A139250, A139251, A152980, A153006, A160117, A160118, A160410, A160412, A160414. %Y A160416 Cf. A160796, A161417. [From _Omar E. Pol_, Jun 14 2009] %K A160416 nonn %O A160416 0,3 %A A160416 _Omar E. Pol_, May 20 2009, Jun 14 2009