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 A265122 #20 Feb 16 2025 08:33:27
%S A265122 1,0,10101,0,101111101,10001000,1010001000101,1000100000,
%T A265122 10111000100011101,1010100010101000,101000000010000000101,
%U A265122 111110001111100000,1011101000101010001011101,101000100000001000101000,10100000100011111000100000101,11100010100010100011100000
%N A265122 Binary representation of the n-th iteration of the "Rule 73" elementary cellular automaton starting with a single ON (black) cell.
%D A265122 S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
%H A265122 Robert Price, <a href="/A265122/b265122.txt">Table of n, a(n) for n = 0..999</a>
%H A265122 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ElementaryCellularAutomaton.html">Elementary Cellular Automaton</a>
%H A265122 S. Wolfram, <a href="http://wolframscience.com/">A New Kind of Science</a>
%H A265122 <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%H A265122 <a href="https://oeis.org/wiki/Index_to_Elementary_Cellular_Automata">Index to Elementary Cellular Automata</a>
%e A265122 From _Michael De Vlieger_, Dec 02 2015: (Start)
%e A265122 First 8 rows, showing surrounding context at left, cells generated by the initial cell at center, and the binary equivalent at right where leading zeros are lost:
%e A265122 0 1 -> 1
%e A265122 1 0 0 0 -> 0
%e A265122 0 1 0 1 0 1 -> 10101
%e A265122 1 0 0 0 0 0 0 0 -> 0
%e A265122 0 1 0 1 1 1 1 1 0 1 -> 101111101
%e A265122 1 0 0 0 1 0 0 0 1 0 0 0 -> 10001000
%e A265122 0 1 0 1 0 0 0 1 0 0 0 1 0 1 -> 1010001000101
%e A265122 1 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 -> 1000100000
%e A265122 0 1 0 1 1 1 0 0 0 1 0 0 0 1 1 1 0 1 -> 10111000100011101
%e A265122 (End)
%t A265122 rule = 73; rows = 20; Table[FromDigits[Table[Take[CellularAutomaton[rule,{{1},0}, rows-1, {All,All}][[k]], {rows-k+1, rows+k-1}], {k,1,rows}][[k]]], {k,1,rows}]
%Y A265122 Cf. A245549.
%K A265122 nonn,easy
%O A265122 0,3
%A A265122 _Robert Price_, Dec 01 2015