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A267276
Decimal representation of the n-th iteration of the "Rule 118" elementary cellular automaton starting with a single ON (black) cell.
1
1, 7, 19, 123, 283, 1883, 5083, 30939, 72411, 483035, 1296091, 7919323, 18544347, 123614939, 331790043, 2027402971, 4747015899, 31645349595, 84938700507, 519012464347, 1215235471067, 8101213091547, 21744285759195, 132867186079451, 311100309354203
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
FORMULA
Empirical g.f.: (1+6*x+12*x^2+96*x^3-144*x^4-32*x^5-704*x^6) / ((1-x)*(1-2*x)*(1-4*x)*(1+4*x)*(1+2*x+4*x^2)*(1+16*x^2)). - Colin Barker, Jan 14 2016 and Apr 19 2019
MATHEMATICA
rule=118; 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 *) Table[FromDigits[catri[[k]], 2], {k, 1, rows}] (* Decimal Representation of Rows *)
CROSSREFS
Cf. A071034.
Sequence in context: A070976 A249608 A265281 * A328713 A376907 A096321
KEYWORD
nonn
AUTHOR
Robert Price, Jan 12 2016
STATUS
approved