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A273760 Partial sums of the number of active (ON,black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 902", based on the 5-celled von Neumann neighborhood. 1
1, 6, 11, 28, 37, 66, 83, 144, 165, 230, 283, 388, 453, 590, 671, 904, 1013, 1230, 1359, 1696, 1869, 2182, 2439, 2868, 3185, 3682, 4023, 4668, 5061, 5762, 6231, 7008, 7705, 8438, 9143, 10148, 10837, 11682, 12523, 13688, 14617, 15850, 16959, 18172, 19273 (list; graph; refs; listen; history; text; internal format)
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.

LINKS

Robert Price, Table of n, a(n) for n = 0..128

N. J. A. Sloane, On the Number of ON Cells in Cellular Automata, arXiv:1503.01168 [math.CO], 2015

Eric Weisstein's World of Mathematics, Elementary Cellular Automaton

S. Wolfram, A New Kind of Science

Index entries for sequences related to cellular automata

Index to 2D 5-Neighbor Cellular Automata

Index to Elementary Cellular Automata

MATHEMATICA

CAStep[rule_, a_]:=Map[rule[[10-#]]&, ListConvolve[{{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}, a, 2], {2}];

code=902; 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. A273758.

Sequence in context: A087737 A273328 A273423 * A273837 A273409 A273484

Adjacent sequences:  A273757 A273758 A273759 * A273761 A273762 A273763

KEYWORD

nonn,easy

AUTHOR

Robert Price, May 29 2016

STATUS

approved

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Last modified May 25 17:19 EDT 2020. Contains 334595 sequences. (Running on oeis4.)