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A267879 Binary representation of the middle column of the "Rule 233" elementary cellular automaton starting with a single ON (black) cell. 1
1, 10, 101, 1010, 10101, 101011, 1010111, 10101111, 101011111, 1010111111, 10101111111, 101011111111, 1010111111111, 10101111111111, 101011111111111, 1010111111111111, 10101111111111111, 101011111111111111, 1010111111111111111, 10101111111111111111 (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

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

FORMULA

Conjectures from Colin Barker, Jan 22 2016 and Apr 20 2019: (Start)

a(n) = 11*a(n-1)-10*a(n-2) for n>4.

G.f.: (1-x+x^2-x^3+x^4) / ((1-x)*(1-10*x)).

(End)

MATHEMATICA

rule=233; 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]], {k, 1, rows}]  (* Binary Representation of Middle Column *)

CROSSREFS

Cf. A267868.

Sequence in context: A279665 A266247 A267443 * A284137 A284179 A096883

Adjacent sequences:  A267876 A267877 A267878 * A267880 A267881 A267882

KEYWORD

nonn,easy

AUTHOR

Robert Price, Jan 21 2016

STATUS

approved

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Last modified July 16 23:49 EDT 2019. Contains 325092 sequences. (Running on oeis4.)