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

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A200573 Number of n X 2 0..2 arrays with no average of any element and its horizontal and vertical neighbors equal to one. 1
6, 36, 174, 922, 5202, 29180, 163706, 919924, 5171420, 29068726, 163403454, 918546962, 5163485576, 29025793202, 163164480016, 917206531060, 5155949803838, 28983459159770, 162926511803678, 915868877073788 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

Robert Israel, Maple-assisted proof of empirical formula

FORMULA

Empirical: a(n) = 5*a(n-1) +8*a(n-2) -20*a(n-3) -23*a(n-4) -52*a(n-5) +25*a(n-6) +254*a(n-7) +62*a(n-8) -134*a(n-9) -88*a(n-10) -360*a(n-11) +176*a(n-12) -168*a(n-13) +184*a(n-14).

Empirical formula confirmed by Robert Israel, Jun 28 2018 (see link).

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Column 2 of A200579.

Sequence in context: A213294 A293886 A132165 * A224130 A283197 A218265

Adjacent sequences:  A200570 A200571 A200572 * A200574 A200575 A200576

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 19 2011

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 December 3 21:17 EST 2021. Contains 349468 sequences. (Running on oeis4.)