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A266660 Binary representation of the n-th iteration of the "Rule 47" elementary cellular automaton starting with a single ON (black) cell. 1
1, 110, 11, 1111100, 11, 11111111100, 11, 111111111111100, 11, 1111111111111111100, 11, 11111111111111111111100, 11, 111111111111111111111111100, 11, 1111111111111111111111111111100, 11, 11111111111111111111111111111111100, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

REFERENCES

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

LINKS

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

FORMULA

Conjectures from Colin Barker, Jan 03 2016 and Apr 18 2019: (Start)

a(n) = (199*(-1)^n+10^(2*n+1)-(-1)^n*10^(2*n+1)-1)/18 for n>1.

a(n) = 10001*a(n-2)-10000*a(n-4) for n>5.

G.f.: (1+110*x-9990*x^2+10990*x^3-100000*x^4+100000*x^5) / ((1-x)*(1+x)*(1-100*x)*(1+100*x)).

(End)

a(n) = A266254(n), n>1. - R. J. Mathar, Jan 10 2016

MATHEMATICA

rule=47; 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 *)

CROSSREFS

Cf. A266659.

Sequence in context: A286172 A282074 A282325 * A087303 A045884 A247391

Adjacent sequences:  A266657 A266658 A266659 * A266661 A266662 A266663

KEYWORD

nonn,easy

AUTHOR

Robert Price, Jan 02 2016

STATUS

approved

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Last modified April 4 07:32 EDT 2020. Contains 333213 sequences. (Running on oeis4.)