A252153 Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 1 3 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 1 3 6 or 7

3583, 2702, 4988, 8425, 15460, 29825, 58792, 116276, 229960, 457196, 909868, 1810124, 3610156, 7203020, 14368492, 28697612, 57327052, 114505100, 228854092, 457436876, 914279500, 1827936716, 3654790348, 7307206604, 14611927756

Offset

1,1

Comments

Column 4 of A252157

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -2*a(n-2) +6*a(n-3) -18*a(n-4) +12*a(n-5) -8*a(n-6) +24*a(n-7) -16*a(n-8) for n>13

Example

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

Crossrefs

Sequence in context: A004952 A004972 A246855 * A234138 A249289 A249537

Adjacent sequences: A252150 A252151 A252152 * A252154 A252155 A252156

Keyword

nonn

Author

R. H. Hardin, Dec 14 2014

Status

approved