A267208 - OEIS

A267208

Middle column of the "Rule 109" elementary cellular automaton starting with a single ON (black) cell.

1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1

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OFFSET

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

MATHEMATICA

rule=109; 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[catri[[k]][[k]], {k, 1, rows}] (* Keep only middle cell from each row *)

CROSSREFS

Cf. A243566.

Apart from initial terms, appears to be essentially the same as A204418 and A011655. - R. J. Mathar, Jan 17 2016

Sequence in context: A267576 A156707 A131309 * A106510 A163806 A163810

Adjacent sequences: A267205 A267206 A267207 * A267209 A267210 A267211

KEYWORD

nonn,easy

AUTHOR

Robert Price, Jan 11 2016

STATUS

approved