login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A267689 Decimal representation of the n-th iteration of the "Rule 199" elementary cellular automaton starting with a single ON (black) cell. 1
1, 6, 28, 122, 500, 2026, 8148, 32682, 130900, 523946, 2096468, 8387242, 33551700, 134212266, 536859988, 2147461802, 8589890900, 34359650986, 137438778708, 549755464362, 2199022556500, 8796091624106, 35184369292628, 140737482762922, 562949942236500 (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 19 2016 and Apr 20 2019: (Start)

a(n) = 6*a(n-1)-7*a(n-2)-6*a(n-3)+8*a(n-4) for n>4.

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

(End)

Empirical a(n) = -1 -(-1)^n/3 - 2^(1+n)/3 + 2^(1+2*n) for n>0. - Colin Barker, Feb 14 2017 and Apr 20 2019

MATHEMATICA

rule=199; 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 *) Table[FromDigits[catri[[k]], 2], {k, 1, rows}]   (* Decimal Representation of Rows *)

CROSSREFS

Cf. A267687.

Sequence in context: A292485 A225417 A026851 * A300996 A181337 A002693

Adjacent sequences:  A267686 A267687 A267688 * A267690 A267691 A267692

KEYWORD

nonn,easy

AUTHOR

Robert Price, Jan 19 2016

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 21 08:47 EDT 2019. Contains 328292 sequences. (Running on oeis4.)