A252257 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 3 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 3 6 or 7

1072, 1331, 965, 972, 1086, 1187, 1468, 1936, 2388, 3052, 4008, 5018, 6478, 8548, 10818, 14040, 18564, 23632, 30772, 40702, 52062, 67962, 89866, 115438, 150986, 199570, 257342, 337104, 445444, 576372, 755968, 998760, 1296302, 1702042

Offset

1,1

Comments

Column 1 of A252260

Links

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

Formula

Empirical: a(n) = 5*a(n-3) +a(n-5) -8*a(n-6) -4*a(n-8) +4*a(n-9) +5*a(n-11) -2*a(n-14) for n>27

Example

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

Crossrefs

Sequence in context: A252256 A345525 A345779 * A252260 A085337 A085338

Adjacent sequences: A252254 A252255 A252256 * A252258 A252259 A252260

Keyword

nonn

Author

R. H. Hardin, Dec 16 2014

Status

approved