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!)
A252382 Number of (n+2) X (6+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 3 5 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 3 5 6 or 7. 1
4682, 1496, 1341, 1475, 1894, 2356, 2778, 3836, 5035, 6189, 8920, 12049, 15119, 22230, 30412, 38498, 57076, 78487, 99705, 148304, 204349, 259947, 387142, 533860, 679466, 1012428, 1396531, 1777781, 2649448, 3655033, 4653207, 6935222, 9567868 (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-3) - 4*a(n-6) + a(n-9) for n>12.

Empirical g.f.: x*(4682 + 1496*x + 1341*x^2 - 17253*x^3 - 4090*x^4 - 3008*x^5 + 15606*x^6 + 2244*x^7 + 975*x^8 - 3705*x^9 - 344*x^10 - 8*x^11) / ((1 - x)*(1 + x + x^2)*(1 - 3*x^3 + x^6)). - Colin Barker, Dec 03 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

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

CROSSREFS

Column 6 of A252384.

Sequence in context: A230487 A230483 A022244 * A190131 A226801 A320620

Adjacent sequences:  A252379 A252380 A252381 * A252383 A252384 A252385

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 17 2014

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 6 01:25 EST 2021. Contains 349558 sequences. (Running on oeis4.)