

A267518


Number of OFF (white) cells in the nth iteration of the "Rule 137" elementary cellular automaton starting with a single ON (black) cell.


1



0, 3, 3, 5, 3, 5, 6, 8, 5, 6, 8, 8, 8, 11, 11, 13, 9, 11, 11, 13, 14, 16, 14, 14, 13, 13, 17, 22, 20, 16, 17, 24, 19, 14, 19, 25, 18, 20, 25, 24, 19, 24, 31, 27, 26, 24, 22, 32, 31, 28, 24, 29, 34, 30, 31, 37, 34, 34, 36, 35, 34, 35, 36, 43, 40, 36, 38, 37
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OFFSET

0,2


REFERENCES

S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.


LINKS

Robert Price, Table of n, a(n) for n = 0..1000
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 Elementary Cellular Automata


MATHEMATICA

rule=137; rows=20; ca=CellularAutomaton[rule, {{1}, 0}, rows1, {All, All}]; (* Start with single black cell *) catri=Table[Take[ca[[k]], {rowsk+1, rows+k1}], {k, 1, rows}]; (* Truncated list of each row *) nbc=Table[Total[catri[[k]]], {k, 1, rows}]; (* Number of Black cells in stage n *) Table[Length[catri[[k]]]nbc[[k]], {k, 1, rows}] (* Number of White cells in stage n *)


CROSSREFS

Cf. A071049, A267463.
Sequence in context: A178984 A065507 A182731 * A101772 A233793 A158894
Adjacent sequences: A267515 A267516 A267517 * A267519 A267520 A267521


KEYWORD

nonn,easy


AUTHOR

Robert Price, Jan 16 2016


STATUS

approved



