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A267923 Binary representation of the n-th iteration of the "Rule 245" elementary cellular automaton starting with a single ON (black) cell. 1
1, 11, 11011, 1111011, 111111011, 11111111011, 1111111111011, 111111111111011, 11111111111111011, 1111111111111111011, 111111111111111111011, 11111111111111111111011, 1111111111111111111111011, 111111111111111111111111011, 11111111111111111111111111011 (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 23 2016 and Apr 20 2019: (Start)

a(n) = 101*a(n-1)-100*a(n-2) for n>2.

G.f.: (1-90*x+10000*x^2) / ((1-x)*(1-100*x)).

(End)

MATHEMATICA

rule=245; 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. A267922.

Sequence in context: A118557 A267273 A138713 * A068223 A068224 A066945

Adjacent sequences:  A267920 A267921 A267922 * A267924 A267925 A267926

KEYWORD

nonn,easy

AUTHOR

Robert Price, Jan 22 2016

STATUS

approved

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Last modified September 16 11:11 EDT 2019. Contains 327095 sequences. (Running on oeis4.)