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A267800
Triangle read by rows giving successive states of cellular automaton generated by "Rule 213" initiated with a single ON (black) cell.
5
1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1
OFFSET
0
COMMENTS
Row n has length 2n+1.
EXAMPLE
The first ten rows:
1
0 1 1
1 0 0 1 1
1 1 1 0 0 1 1
1 1 1 1 1 0 0 1 1
1 1 1 1 1 1 1 0 0 1 1
1 1 1 1 1 1 1 1 1 0 0 1 1
1 1 1 1 1 1 1 1 1 1 1 0 0 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 1
MATHEMATICA
rule=213; 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
Cf. A267537 (central column), A267533 (row reversals).
Sequence in context: A307243 A120530 A078616 * A373993 A322980 A267053
KEYWORD
nonn,tabf,easy
AUTHOR
Robert Price, Jan 20 2016
STATUS
approved