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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, 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
1,4
COMMENTS
Row 10 of A187586
FORMULA
Empirical: a(n) = 108852*n^2 - 978404*n + 2100276 for n>8
EXAMPLE
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
CROSSREFS
Sequence in context: A090056 A229410 A257356 * A230923 A137839 A343373
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 11 2011
STATUS
approved