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A267015
Triangle read by rows giving successive states of cellular automaton generated by "Rule 91" initiated with a single ON (black) cell.
10
1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 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
1 0 1
0 1 0 1 0
1 1 0 0 0 1 1
0 0 1 1 1 1 1 0 0
1 1 1 1 0 0 0 1 1 1 1
0 0 0 0 1 1 1 1 1 0 0 0 0
1 1 1 1 1 1 0 0 0 1 1 1 1 1 1
0 0 0 0 0 0 1 1 1 1 1 0 0 0 0 0 0
1 1 1 1 1 1 1 1 0 0 0 1 1 1 1 1 1 1 1
MATHEMATICA
rule=91; 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: A117569 A135528 A163805 * A078387 A189292 A331168
KEYWORD
nonn,tabf,easy
AUTHOR
Robert Price, Jan 09 2016
STATUS
approved