login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A265429 Total number of ON (black) cells after n iterations of the "Rule 188" elementary cellular automaton starting with a single ON (black) cell. 3
1, 3, 5, 9, 13, 18, 23, 30, 37, 45, 53, 63, 73, 84, 95, 108, 121, 135, 149, 165, 181, 198, 215, 234, 253, 273, 293, 315, 337, 360, 383, 408, 433, 459, 485, 513, 541, 570, 599, 630, 661, 693, 725, 759, 793, 828, 863, 900, 937, 975, 1013, 1053, 1093, 1134 (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
Eric Weisstein's World of Mathematics, Elementary Cellular Automaton
FORMULA
Conjectures from Colin Barker, Dec 09 2015 and Apr 16 2019: (Start)
a(n) = (1/16)*(6*n^2 + 24*n - 3*(-1)^n + 2*(-i)^n + 2*i^n + 15) where i = sqrt(-1).
G.f.: (1 + x + 2*x^3 - x^4) / ((1-x)^3*(1+x)*(1+x^2)).
(End)
Conjecture: the sequence consists of all numbers k > 0 such that floor(sqrt(8*(k+1)/3)) != floor(sqrt(8*k/3)). - Gevorg Hmayakyan, Sep 01 2019
EXAMPLE
From Michael De Vlieger, Dec 09 2015: (Start)
First 12 rows, replacing "0" with ".", ignoring "0" outside of range of 1's for better visibility of ON cells, followed by total number of ON cells per row, and running total up to that row:
1 = 1 -> 1
1 1 = 2 -> 3
1 . 1 = 2 -> 5
1 1 1 1 = 4 -> 9
1 1 1 . 1 = 4 -> 13
1 1 . 1 1 1 = 5 -> 18
1 . 1 1 1 . 1 = 5 -> 23
1 1 1 1 . 1 1 1 = 7 -> 30
1 1 1 . 1 1 1 . 1 = 7 -> 37
1 1 . 1 1 1 . 1 1 1 = 8 -> 45
1 . 1 1 1 . 1 1 1 . 1 = 8 -> 53
1 1 1 1 . 1 1 1 . 1 1 1 = 10 -> 63
1 1 1 . 1 1 1 . 1 1 1 . 1 = 10 -> 72
(End)
MATHEMATICA
rule = 188; rows = 30; Table[Total[Take[Table[Total[Table[Take[CellularAutomaton[rule, {{1}, 0}, rows-1, {All, All}][[k]], {rows-k+1, rows+k-1}], {k, 1, rows}][[k]]], {k, 1, rows}], k]], {k, 1, rows}]
Accumulate[Count[#, n_ /; n == 1] & /@ CellularAutomaton[188, {{1}, 0}, 53]] (* Michael De Vlieger, Dec 09 2015 *)
CROSSREFS
Cf. A118174.
Sequence in context: A032635 A036713 A260733 * A356254 A122248 A024403
KEYWORD
nonn,easy
AUTHOR
Robert Price, Dec 08 2015
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 19 12:14 EDT 2024. Contains 371792 sequences. (Running on oeis4.)