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A267443
Binary representation of the middle column of the "Rule 129" elementary cellular automaton starting with a single ON (black) cell.
1
1, 10, 101, 1010, 10101, 101011, 1010111, 10101110, 101011101, 1010111011, 10101110111, 101011101111, 1010111011111, 10101110111111, 101011101111111, 1010111011111110, 10101110111111101, 101011101111111011, 1010111011111110111, 10101110111111101111
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=129; 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 *) mc=Table[catri[[k]][[k]], {k, 1, rows}]; (* Keep only middle cell from each row *) Table[FromDigits[Take[mc, k]], {k, 1, rows}] (* Binary Representation of Middle Column *)
CROSSREFS
Cf. A267417.
Sequence in context: A280146 A279665 A266247 * A267879 A284137 A284179
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 15 2016
STATUS
approved