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A266216
Triangle read by rows giving successive states of cellular automaton generated by "Rule 7" initiated with a single ON (black) cell.
9
1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1
OFFSET
0
COMMENTS
Row n has length 2n+1.
EXAMPLE
The first ten rows:
1
1 1 0
0 0 0 0 0
1 1 1 1 1 1 1
0 0 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1 1 1 1
0 0 0 0 0 0 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
MATHEMATICA
rule=7; 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. A266217, A266218, A266377 (rows reversed).
Sequence in context: A204269 A371690 A179830 * A025446 A373972 A266300
KEYWORD
nonn,tabf,easy
AUTHOR
Robert Price, Dec 24 2015
STATUS
approved