%I #7 Jan 16 2016 10:32:53
%S 1,2,5,10,21,43,87,174,349,699,1399,2799,5599,11199,22399,44798,89597,
%T 179195,358391,716783,1433567,2867135,5734271,11468543,22937087,
%U 45874175,91748351,183496703,366993407,733986815,1467973631,2935947262,5871894525,11743789051
%N Decimal representation of the middle column of the "Rule 129" elementary cellular automaton starting with a single ON (black) cell.
%D S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
%H Robert Price, <a href="/A267444/b267444.txt">Table of n, a(n) for n = 0..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ElementaryCellularAutomaton.html">Elementary Cellular Automaton</a>
%H S. Wolfram, <a href="http://wolframscience.com/">A New Kind of Science</a>
%H <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%H <a href="https://oeis.org/wiki/Index_to_Elementary_Cellular_Automata">Index to Elementary Cellular Automata</a>
%t rule=129; 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 *) mc=Table[catri[[k]][[k]],{k,1,rows}]; (* Keep only middle cell from each row *) Table[FromDigits[Take[mc,k],2],{k,1,rows}] (* Binary Representation of Middle Column *)
%Y Cf. A267417.
%K nonn,easy
%O 0,2
%A _Robert Price_, Jan 15 2016