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A269817
First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 35", based on the 5-celled von Neumann neighborhood.
1
4, 0, 32, -28, 92, -80, 164, -156, 284, -272, 416, -388, 560, -528, 716, -700, 956, -944, 1216, -1188, 1484, -1432, 1728, -1676, 2024, -1976, 2332, -2260, 2648, -2576, 2972, -2940, 3452, -3440, 3968, -3940, 4492, -4440, 4992, -4940, 5540, -5472, 6064, -5956
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=35; 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. A269814.
Sequence in context: A271256 A271057 A269879 * A270021 A270328 A270933
KEYWORD
sign,easy
AUTHOR
Robert Price, Mar 05 2016
STATUS
approved