A187593 Number of 10-step E, S, NW and NE-moving king's tours on an n X n board summed over all starting positions.

0, 0, 0, 3108, 45960, 219432, 609070, 1243461, 2111652, 3201436, 4508924, 6034116, 7777012, 9737612, 11915916, 14311924, 16925636, 19757052, 22806172, 26072996, 29557524, 33259756, 37179692, 41317332, 45672676, 50245724, 55036476, 60044932

Offset: 1

Author

R. H. Hardin Mar 11 2011

Keywords

• nonn

Comments

Row 10 of A187586

Examples

			Some solutions for 4X4
..0..8..9.10....0..7..8..9....0..0..0..2....0..8..9.10....0..0..0..0
..1..0..7..0....0..0..6.10....0..7..1..3....0..2..7..0....1..0..7..8
..2..0..5..6....2..3..4..5....0..8..6..4....0..3..1..6....2..6..0..9
..3..4..0..0....0..1..0..0....0..9.10..5....0..4..5..0....3..4..5.10
		

Formula

Empirical: a(n) = 108852*n^2 - 978404*n + 2100276 for n>8