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Binary representation of the n-th iteration of the "Rule 105" elementary cellular automaton starting with a single ON (black) cell.
1

%I #7 Jan 12 2016 00:03:18

%S 1,0,10101,10100,100010001,10001000,1010001000101,1001000100100,

%T 10000000100000001,1111100011111000,101010001010100010101,

%U 101001001010010010100,1000100000001000000010001,100011111000111110001000,10100010100010101000101000101

%N Binary representation of the n-th iteration of the "Rule 105" 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="/A267146/b267146.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=105; 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 *) Table[FromDigits[catri[[k]]],{k,1,rows}] (* Binary Representation of Rows *)

%Y Cf. A267145.

%K nonn,easy

%O 0,3

%A _Robert Price_, Jan 11 2016