login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A206111 Number of (n+1) X 2 0..3 arrays with every 2 X 3 or 3 X 2 subblock having exactly two counterclockwise and two clockwise edge increases. 1
256, 1140, 6028, 31756, 171564, 973388, 5538732, 31668844, 182723180, 1055476940, 6101167404, 35321975916, 204551559276, 1184692892236, 6863075460012, 39761220992620, 230360296104556, 1334668498415052, 7732945730535980 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A206118.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 5*a(n-1) + 5*a(n-2) + 29*a(n-3) - 142*a(n-4) - 248*a(n-5) + 88*a(n-6) + 144*a(n-7).

Empirical g.f.: 4*x*(64 - 35*x - 238*x^2 - 2877*x^3 - 3516*x^4 + 1836*x^5 + 2304*x^6) / ((1 - 2*x - 4*x^2)*(1 - 3*x - 7*x^2 - 55*x^3 + 4*x^4 + 36*x^5)). - Colin Barker, Jun 13 2018

EXAMPLE

Some solutions for n=4:

..1..3....3..1....3..3....0..1....1..2....0..0....2..0....3..3....2..2....1..0

..2..1....1..1....0..1....0..0....1..1....1..0....2..2....0..0....1..0....0..0

..1..1....3..3....0..2....0..1....3..3....0..1....1..1....2..2....3..0....0..3

..1..2....3..1....0..1....3..0....0..3....1..1....0..1....3..2....1..0....1..0

..0..1....0..3....2..2....3..0....3..0....3..1....1..2....0..3....3..3....1..0

CROSSREFS

Cf. A206118.

Sequence in context: A237299 A237293 A206118 * A237211 A237204 A237007

Adjacent sequences:  A206108 A206109 A206110 * A206112 A206113 A206114

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 03 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 22 13:36 EST 2020. Contains 331149 sequences. (Running on oeis4.)