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A266841 Binary representation of the n-th iteration of the "Rule 69" elementary cellular automaton starting with a single ON (black) cell. 1
1, 10, 10100, 101011, 101010000, 1010101111, 1010101000000, 10101010111111, 10101010100000000, 101010101011111111, 101010101010000000000, 1010101010101111111111, 1010101010101000000000000, 10101010101010111111111111, 10101010101010100000000000000 (list; graph; refs; listen; history; text; internal format)



S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.


Robert Price, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Elementary Cellular Automaton

S. Wolfram, A New Kind of Science

Index entries for sequences related to cellular automata

Index to Elementary Cellular Automata


Conjectures from Colin Barker, Jan 05 2016 and Apr 18 2019: (Start)

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

G.f.: (1+10*x-x^2+x^3-110000*x^5) / ((1-x)*(1+x)*(1-10*x)*(1+10*x)*(1-100*x)*(1+100*x)).



rule=69; 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 *)


Cf. A266840.

Sequence in context: A317959 A119037 A327232 * A267677 A101305 A001098

Adjacent sequences:  A266838 A266839 A266840 * A266842 A266843 A266844




Robert Price, Jan 04 2016



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Last modified December 10 20:38 EST 2019. Contains 329909 sequences. (Running on oeis4.)