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!)
A234816 Number of (n+1) X (1+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 6 (constant stress 1 X 1 tilings). 1
168, 686, 2380, 9716, 34092, 139112, 493348, 2011808, 7205628, 29360336, 106119940, 432009296, 1574462652, 6403264112, 23513001988, 95527797008, 353173605948, 1433355470576, 5331803584900, 21616468994576, 80854559348412 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) + 41*a(n-2) - 164*a(n-3) - 558*a(n-4) + 2232*a(n-5) + 2520*a(n-6) - 10080*a(n-7).

Empirical g.f.: 2*x*(84 + 7*x - 3626*x^2 - 189*x^3 + 51948*x^4 + 1260*x^5 - 246960*x^6) / ((1 - 4*x)*(1 - 12*x^2)*(1 - 14*x^2)*(1 - 15*x^2)). - Colin Barker, Oct 16 2018

EXAMPLE

Some solutions for n=5:

..6..2....0..4....5..3....2..0....0..6....4..1....2..3....3..3....6..0....3..1

..0..2....2..0....1..5....2..6....6..6....0..3....6..1....6..0....2..2....0..4

..6..2....0..4....2..0....6..4....0..6....6..3....0..1....3..3....6..0....3..1

..4..6....3..1....0..4....2..6....1..1....3..6....5..0....6..0....4..4....0..4

..4..0....2..6....2..0....2..0....6..0....4..1....4..5....4..4....6..0....6..4

..0..2....2..0....2..6....2..6....0..0....3..6....6..1....6..0....2..2....1..5

CROSSREFS

Column 1 of A234823.

Sequence in context: A234731 A157998 A234823 * A245868 A251461 A110285

Adjacent sequences:  A234813 A234814 A234815 * A234817 A234818 A234819

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 31 2013

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 05:58 EDT 2022. Contains 354048 sequences. (Running on oeis4.)