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A269756
First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 30", based on the 5-celled von Neumann neighborhood.
1
4, 7, 4, 20, -12, 36, -16, 72, -72, 84, -8, 80, -56, 116, -16, 52, -28, 100, 24, -4, -4, 108, 100, -28, -60, 252, 36, -36, -44, 180, 168, -224, 40, 276, 148, -76, -132, 220, 376, -292, -84, 472, 192, -300, -32, 340, 344, -240, -236, 524, 440, -472, -268, 756
OFFSET
0,1
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
rule=30; stages=300;
ca=CellularAutomaton[{rule, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, stages]; (* Start with single black cell *)
on=Map[Function[Apply[Plus, Flatten[#1]]], ca] (* Count ON cells at each stage *)
Table[on[[i+1]]-on[[i]], {i, 1, Length[on]-1}] (* Difference at each stage *)
CROSSREFS
Cf. A269753.
Sequence in context: A101159 A339948 A270136 * A166530 A011518 A132265
KEYWORD
sign,easy
AUTHOR
Robert Price, Mar 04 2016
STATUS
approved