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 A267369 #8 Feb 16 2025 08:33:29
%S A267369 0,0,1,1,6,9,14,14,27,38,51,58,75,86,99,99,128,155,184,207,240,267,
%T A267369 296,311,352,387,424,447,488,515,544,544,605,664,725,780,845,904,965,
%U A267369 1012,1085,1152,1221,1276,1349,1408,1469,1500,1589,1672,1757,1828,1917
%N A267369 Total number of OFF (white) cells after n iterations of the "Rule 126" elementary cellular automaton starting with a single ON (black) cell.
%D A267369 S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
%H A267369 Robert Price, <a href="/A267369/b267369.txt">Table of n, a(n) for n = 0..1000</a>
%H A267369 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ElementaryCellularAutomaton.html">Elementary Cellular Automaton</a>
%H A267369 S. Wolfram, <a href="http://wolframscience.com/">A New Kind of Science</a>
%H A267369 <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%H A267369 <a href="https://oeis.org/wiki/Index_to_Elementary_Cellular_Automata">Index to Elementary Cellular Automata</a>
%t A267369 rule=126; rows=20; ca=CellularAutomaton[rule,{{1},0},rows-1,{All,All}]; (* Start with single black cell *) catri=Table[Take[ca[[k]],{rows-k+1,rows+k-1}],{k,1,rows}]; (* Truncated list of each row *) nbc=Table[Total[catri[[k]]],{k,1,rows}]; (* Number of Black cells in stage n *) nwc=Table[Length[catri[[k]]]-nbc[[k]],{k,1,rows}]; (* Number of White cells in stage n *) Table[Total[Take[nwc,k]],{k,1,rows}] (* Number of White cells through stage n *)
%Y A267369 Cf. A071035.
%K A267369 nonn,easy
%O A267369 0,5
%A A267369 _Robert Price_, Jan 13 2016