A187384 Number of 10-step S, NW and NE-moving king's tours on an n X n board summed over all starting positions.

0, 0, 0, 280, 3792, 17052, 44464, 92628, 159328, 245946, 350386, 472648, 612732, 770638, 946366, 1139916, 1351288, 1580482, 1827498, 2092336, 2374996, 2675478, 2993782, 3329908, 3683856, 4055626, 4445218, 4852632, 5277868, 5720926, 6181806

Offset

1,4

Comments

Row 10 of A187377.

Links

R. H. Hardin, Table of n, a(n) for n = 1..50

Formula

Empirical: a(n) = 8911*n^2 - 82691*n + 181756 for n>8.

Conjectures from Colin Barker, Apr 24 2018: (Start)

G.f.: 2*x^4*(140 + 1476*x + 3258*x^2 + 2202*x^3 + 3300*x^4 - 1108*x^5 + 691*x^6 - 1048*x^7) / (1 - x)^3.

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>11.

(End)

Crossrefs

Cf. A187377.

Sequence in context: A234452 A297510 A327948 * A297724 A024214 A357248

Adjacent sequences: A187381 A187382 A187383 * A187385 A187386 A187387

Keyword

nonn

Author

R. H. Hardin, Mar 09 2011

Status

approved