A215874 Number of permutations of 0..floor((6*n-2)/2) on odd squares of an 6Xn array such that each row, column, diagonal and (downwards) antidiagonal of odd squares is increasing

1, 1, 1, 8, 50, 1233, 15485, 767560, 14296434, 1124811332

Offset

1,4

Comments

Row 6 of A215870

Links

Table of n, a(n) for n=1..10.

Example

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

Crossrefs

Sequence in context: A295167 A195231 A162236 * A348594 A078304 A000851

Adjacent sequences: A215871 A215872 A215873 * A215875 A215876 A215877

Keyword

nonn

Author

R. H. Hardin Aug 25 2012

Status

approved