A252609 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 3 5 6 or 8 and every 3X3 column and antidiagonal sum not equal to 0 3 5 6 or 8

1051, 1379, 2817, 5304, 14435, 37917, 75859, 213611, 599753, 1195427, 3451701, 10095479, 19984819, 58655670, 176140167, 346827424, 1029346845, 3144314768, 6169315363, 18442681353, 56943954915, 111477238107, 334759247526

Offset

1,1

Comments

Column 2 of A252615

Links

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

Formula

Empirical: a(n) = 37*a(n-3) -445*a(n-6) +2151*a(n-9) -4973*a(n-12) +7261*a(n-15) -8366*a(n-18) +5776*a(n-21) -1440*a(n-24) for n>33

Example

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

Crossrefs

Sequence in context: A204753 A252391 A020389 * A185680 A191858 A353054

Adjacent sequences: A252606 A252607 A252608 * A252610 A252611 A252612

Keyword

nonn

Author

R. H. Hardin, Dec 19 2014

Status

approved