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A078176 Numbers given by the Rule 225 Cellular Automaton. 0
7, 11, 15, 19, 23, 27, 63, 67, 71, 75, 79, 83, 87, 91, 127, 131, 135, 139, 143, 147, 151, 155, 191, 195, 455, 715, 975, 1235, 1495, 1755, 4095, 4099, 4103, 4107, 4111, 4115, 4119, 4123, 4159, 4163, 4167, 4171, 4175, 4179, 4183, 4187, 4223, 4227, 4231, 4235 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Discovered by Stephen Wolfram in 1981.
Binary complement of A267843, the usual decimal representation of Rule 225: ON (black) cells are represented by 0 bits and OFF (white) cells by 1 bits here. The single start bit 0 is omitted. - Georg Fischer, Dec 19 2021
REFERENCES
S. Wolfram, A New Kind of Science, p. 58.
LINKS
Eric Weisstein's World of Mathematics, Elementary Cellular Automaton
FORMULA
Binary Cellular Automaton. {1, 1, 1}, {1, 1, 0}, {1, 0, 1}, {0, 0, 1} produce 1.
a(n) = A267843(n) XOR (2^(2*n+1) - 1) for n >= 1. - Georg Fischer, Dec 19 2021
MATHEMATICA
With[{k = Abs[Drop[CellularAutomaton[225, {{1}, 0}, 100], 1] - 1]}, Table[FromDigits[RotateLeft[k[[n]], n + 2], 2], {n, 1, Length[k]}]]
CROSSREFS
Cf. A267843.
Sequence in context: A248630 A130569 A294294 * A097494 A037136 A023486
KEYWORD
nonn
AUTHOR
Ed Pegg Jr, Nov 20 2002
STATUS
approved

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Last modified March 29 09:59 EDT 2024. Contains 371268 sequences. (Running on oeis4.)