A215868 Number of permutations of 0..floor((n*8-2)/2) on odd squares of an nX8 array such that each row, column, diagonal and (downwards) antidiagonal of odd squares is increasing

1, 14, 110, 3001, 26451, 767560, 6812794, 198409297, 1761748159, 51317680568, 455678075546, 13273519382093, 117863060852067, 3433253982499552, 30485799411892266, 888026282079787049, 7885286478349158743

Offset

1,2

Comments

Column 8 of A215870

Links

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

Formula

Empirical: a(n) = 272*a(n-2) -3439*a(n-4) -3336*a(n-6) +140*a(n-8)

Example

Some solutions for n=4
..x..0..x..2..x..4..x..6....x..0..x..1..x..2..x..7....x..0..x..1..x..3..x..5
..1..x..3..x..7..x..9..x....3..x..4..x..5..x..8..x....2..x..4..x..8..x..9..x
..x..5..x..8..x.10..x.13....x..6..x.10..x.11..x.12....x..6..x.10..x.12..x.14
.11..x.12..x.14..x.15..x....9..x.13..x.14..x.15..x....7..x.11..x.13..x.15..x

Crossrefs

Sequence in context: A294445 A036395 A271561 * A244693 A039630 A234800

Adjacent sequences: A215865 A215866 A215867 * A215869 A215870 A215871

Keyword

nonn

Author

R. H. Hardin Aug 25 2012

Status

approved