A252419 Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 5 6 or 7

1536, 1704, 3796, 6834, 22038, 62288, 113324, 380113, 1090041, 1973072, 6662465, 19166898, 34694777, 117327314, 337764647, 611422010, 2068344465, 5955308893, 10780434860, 36471334123, 105014194820, 190099680839, 643138365330

Offset

1,1

Comments

Column 4 of A252423

Links

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

Formula

Empirical: a(n) = 25*a(n-3) -146*a(n-6) +295*a(n-9) -193*a(n-12) +20*a(n-15) for n>21

Example

Some solutions for n=4
..2..0..1..0..0..1....1..1..2..1..1..2....2..1..1..2..1..1....0..1..0..3..1..0
..0..3..1..0..0..1....0..0..1..3..0..1....1..0..0..1..0..2....0..1..0..0..1..0
..1..1..2..1..1..2....3..0..1..0..0..1....1..0..0..1..3..0....1..2..1..1..2..1
..3..0..1..0..0..1....1..1..2..1..1..2....2..1..1..2..1..1....0..1..0..3..1..0
..0..0..1..3..0..1....0..0..1..3..0..1....1..0..0..1..0..3....0..1..0..0..1..3
..1..1..2..1..1..2....0..3..1..0..0..1....1..3..0..1..0..0....1..2..1..1..2..1

Crossrefs

Sequence in context: A251891 A088362 A045123 * A179692 A105923 A229507

Adjacent sequences: A252416 A252417 A252418 * A252420 A252421 A252422

Keyword

nonn

Author

R. H. Hardin, Dec 17 2014

Status

approved