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A243566
Triangle read by rows giving successive states of cellular automaton generated by "Rule 109" initiated with a single ON (black) cell.
10
1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1
OFFSET
0
COMMENTS
Row n has length 2n+1.
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
EXAMPLE
The first ten rows:
1
0 1 0
1 1 1 1 1
0 1 0 0 0 1 0
1 1 1 0 1 0 1 1 1
0 1 0 1 1 1 1 1 0 1 0
1 1 1 1 1 0 0 0 1 1 1 1 1
0 1 0 0 0 1 0 1 0 1 0 0 0 1 0
1 1 1 0 1 0 1 1 1 1 1 0 1 0 1 1 1
0 1 0 1 1 1 1 1 0 0 0 1 1 1 1 1 0 1 0
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 *) Flatten[catri] (* Triangle Representation of CA *)
CROSSREFS
Sequence in context: A267848 A267179 A244527 * A266112 A331990 A301849
KEYWORD
nonn,tabf,easy
AUTHOR
Robert Price, Jan 11 2016
STATUS
approved