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A266628
Number of OFF (white) cells in the n-th iteration of the "Rule 45" elementary cellular automaton starting with a single ON (black) cell.
1
0, 2, 1, 5, 4, 4, 5, 7, 10, 6, 12, 11, 14, 9, 14, 13, 19, 12, 21, 17, 26, 13, 22, 24, 29, 15, 35, 25, 25, 29, 31, 29, 37, 30, 36, 27, 46, 23, 52, 26, 49, 36, 47, 33, 61, 29, 57, 38, 59, 38, 58, 44, 66, 42, 66, 46, 69, 41, 66, 52, 73, 44, 85, 48, 88, 49, 83
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=45; 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. A266619.
Sequence in context: A159930 A058344 A010582 * A283441 A262219 A249905
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 01 2016
STATUS
approved