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A266625 Decimal representation of the middle column of the "Rule 45" elementary cellular automaton starting with a single ON (black) cell. 1
1, 3, 7, 14, 28, 57, 115, 230, 460, 921, 1842, 3685, 7371, 14743, 29486, 58973, 117947, 235894, 471789, 943579, 1887159, 3774318, 7548637, 15097274, 30194548, 60389097, 120778195, 241556391, 483112783, 966225567, 1932451134, 3864902268, 7729804536 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

REFERENCES

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

LINKS

G. C. Greubel, 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=45; rows=20; ca=CellularAutomaton[rule, {{1}, 0}, rows-1, {All, All}]; (* Start with single black cell *) catri=Table[Take[ca[[k]], {rows-k+1, rows+k-1}], {k, 1, rows}]; (* Truncated list of each row *) mc=Table[catri[[k]][[k]], {k, 1, rows}]; (* Keep only middle cell from each row *) Table[FromDigits[Take[mc, k], 2], {k, 1, rows}]  (* Binary Representation of Middle Column *)

CROSSREFS

Cf. A266619.

Sequence in context: A125176 A153234 A293334 * A151754 A192065 A157672

Adjacent sequences:  A266622 A266623 A266624 * A266626 A266627 A266628

KEYWORD

nonn,easy

AUTHOR

Robert Price, Jan 01 2016

STATUS

approved

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Last modified July 4 11:58 EDT 2020. Contains 335448 sequences. (Running on oeis4.)