The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
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!)
A206679 Number of (n+1) X 3 0..2 arrays with every 2 X 3 or 3 X 2 subblock having an unequal number of clockwise and counterclockwise edge increases. 1
306, 1728, 9792, 55836, 317736, 1809324, 10300608, 58646916, 333899064, 1901032092, 10823363424, 61621963812, 350839639224, 1997477224380, 11372475138624, 64748269110564, 368639041055544, 2098816612656732 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 2 of A206685.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) + 13*a(n-2) + 11*a(n-3) + 12*a(n-4) + 6*a(n-5) for n>6.
Empirical g.f.: 18*x*(17 + 45*x + 35*x^2 + 35*x^3 + 14*x^4 - 2*x^5) / (1 - 3*x - 13*x^2 - 11*x^3 - 12*x^4 - 6*x^5). - Colin Barker, Jun 17 2018
EXAMPLE
Some solutions for n=4:
..0..1..1....0..0..0....1..0..2....2..2..2....0..0..2....0..1..2....0..1..2
..2..1..0....1..1..2....1..1..1....1..0..2....2..0..1....0..2..2....1..0..0
..1..1..2....0..2..0....2..0..1....1..0..1....1..0..0....0..0..1....1..2..2
..2..0..1....2..2..1....2..2..1....1..2..0....1..1..2....1..2..0....0..1..0
..0..0..2....0..1..2....1..0..2....1..1..1....0..2..1....2..1..0....0..2..1
CROSSREFS
Cf. A206685.
Sequence in context: A236012 A158589 A030030 * A172966 A223073 A064257
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 11 2012
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 May 25 12:29 EDT 2024. Contains 372788 sequences. (Running on oeis4.)