A252426 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 4 6 or 7

641, 602, 608, 878, 1152, 1603, 2617, 4131, 6514, 11116, 18318, 29859, 51493, 85589, 140525, 243028, 404779, 665504, 1151754, 1919298, 3156379, 5463943, 9106163, 14976103, 25929380, 43214599, 71070066, 123069528, 205112198, 337314463

Offset

1,1

Comments

Column 1 of A252433

Links

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

Formula

Empirical: a(n) = 11*a(n-3) -39*a(n-6) +57*a(n-9) -72*a(n-12) +60*a(n-15) -31*a(n-18) +17*a(n-21) -a(n-24) -a(n-27) for n>34

Example

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

Crossrefs

Sequence in context: A170774 A290029 A268875 * A256777 A252425 A160203

Adjacent sequences: A252423 A252424 A252425 * A252427 A252428 A252429

Keyword

nonn

Author

R. H. Hardin, Dec 17 2014

Status

approved