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A267208
Middle column of the "Rule 109" elementary cellular automaton starting with a single ON (black) cell.
1
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
OFFSET
0
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
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
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 11 2016
STATUS
approved