A215875 Number of permutations of 0..floor((7*n-2)/2) on odd squares of an 7Xn array such that each row, column, diagonal and (downwards) antidiagonal of odd squares is increasing.

1, 1, 1, 8, 100, 2988, 97289, 6812794, 386699176, 48337803306

Offset: 1

Author

R. H. Hardin Aug 25 2012

Keywords

• nonn

Comments

Row 7 of A215870

Examples

			Some solutions for n=4
..x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..2....x..0..x..2
..2..x..3..x....2..x..3..x....2..x..3..x....1..x..3..x....1..x..3..x
..x..4..x..5....x..4..x..5....x..4..x..6....x..4..x..6....x..4..x..5
..6..x..7..x....6..x..7..x....5..x..7..x....5..x..7..x....6..x..7..x
..x..8..x..9....x..8..x.10....x..8..x..9....x..8..x.10....x..8..x..9
.10..x.11..x....9..x.11..x...10..x.11..x....9..x.11..x...10..x.11..x
..x.12..x.13....x.12..x.13....x.12..x.13....x.12..x.13....x.12..x.13