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A267592
Number of OFF (white) cells in the n-th iteration of the "Rule 169" elementary cellular automaton starting with a single ON (black) cell.
1
0, 3, 3, 4, 3, 4, 4, 6, 3, 4, 4, 5, 4, 5, 5, 7, 3, 4, 4, 5, 4, 5, 5, 7, 4, 6, 6, 8, 6, 8, 8, 12, 3, 4, 4, 5, 4, 5, 5, 7, 4, 5, 5, 6, 5, 6, 6, 8, 4, 5, 5, 6, 5, 6, 6, 8, 5, 7, 7, 9, 7, 9, 9, 13, 3, 4, 4, 5, 4, 5, 5, 7, 4, 5, 5, 6, 5, 6, 6, 8, 4, 5, 5, 6, 5, 6
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=169; 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 *) nbc=Table[Total[catri[[k]]], {k, 1, rows}]; (* Number of Black cells in stage n *) Table[Length[catri[[k]]]-nbc[[k]], {k, 1, rows}] (* Number of White cells in stage n *)
CROSSREFS
Cf. A264442.
Sequence in context: A046537 A167596 A216190 * A243341 A238856 A096139
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 18 2016
STATUS
approved