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A271307
Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 353", based on the 5-celled von Neumann neighborhood.
1
1, 5, 14, 46, 59, 143, 164, 336, 361, 633, 682, 1090, 1171, 1743, 1816, 2620, 2749, 3705, 3870, 5130, 5291, 6811, 7000, 8804, 9017, 11141, 11362, 13878, 14183, 16995, 17384, 20652, 21025, 24629, 25042, 29158, 29623, 34315, 34784, 39852, 40385, 46121, 46810
OFFSET
0,2
COMMENTS
Initialized with a single black (ON) cell at stage zero.
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 170.
MATHEMATICA
CAStep[rule_, a_]:=Map[rule[[10-#]]&, ListConvolve[{{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}, a, 2], {2}];
code=353; stages=128;
rule=IntegerDigits[code, 2, 10];
g=2*stages+1; (* Maximum size of grid *)
a=PadLeft[{{1}}, {g, g}, 0, Floor[{g, g}/2]]; (* Initial ON cell on grid *)
ca=a;
ca=Table[ca=CAStep[rule, ca], {n, 1, stages+1}];
PrependTo[ca, a];
(* Trim full grid to reflect growth by one cell at each stage *)
k=(Length[ca[[1]]]+1)/2;
ca=Table[Table[Part[ca[[n]][[j]], Range[k+1-n, k-1+n]], {j, k+1-n, k-1+n}], {n, 1, k}];
on=Map[Function[Apply[Plus, Flatten[#1]]], ca] (* Count ON cells at each stage *)
Table[Total[Part[on, Range[1, i]]], {i, 1, Length[on]}] (* Sum at each stage *)
CROSSREFS
Cf. A271305.
Sequence in context: A222908 A270911 A270154 * A270162 A271416 A270179
KEYWORD
nonn,easy
AUTHOR
Robert Price, Apr 03 2016
STATUS
approved