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Binary representation of the n-th iteration of the "Rule 79" elementary cellular automaton starting with a single ON (black) cell.
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%I #21 Jun 13 2022 14:51:34

%S 1,110,101,1111010,10101,11111101010,1010101,111111110101010,

%T 101010101,1111111111010101010,10101010101,11111111111101010101010,

%U 1010101010101,111111111111110101010101010,101010101010101,1111111111111111010101010101010,10101010101010101

%N Binary representation of the n-th iteration of the "Rule 79" 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="/A266979/b266979.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>

%F Conjectures from _Colin Barker_, Jan 08 2016 and Apr 18 2019: (Start)

%F a(n) = 10101*a(n-2)-1010100*a(n-4)+1000000*a(n-6) for n>5.

%F G.f.: (1+110*x-10000*x^2-100*x^3-100000*x^5) / ((1-x)*(1+x)*(1-10*x)*(1+10*x)*(1-100*x)*(1+100*x)).

%F (End)

%t rule=79; 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. A266978, A266980.

%K nonn,easy

%O 0,2

%A _Robert Price_, Jan 07 2016

%E Removed an unjustified claim that _Colin Barker_'s conjectures are correct. Removed a program based on a conjecture. - _Michael De Vlieger_, Jun 13 2022