A201237 Number of ways to place 3 non-attacking wazirs on an n X n toroidal board.

0, 0, 6, 208, 1300, 4908, 14112, 34112, 73008, 142700, 259908, 447312, 734812, 1160908, 1774200, 2635008, 3817112, 5409612, 7518908, 10270800, 13812708, 18316012, 23978512, 31027008, 39720000, 50350508, 63249012, 78786512, 97377708, 119484300, 145618408

Offset

1,3

Comments

A wazir is a leaper [0,1].

Links

Table of n, a(n) for n=1..31.

V. Kotesovec, Non-attacking chess pieces, 6ed, p.402

Formula

a(n) = n^2*(n^4-15*n^2+62)/6, n>=4.

G.f.: -2*x^3 * (3*x^7 - 15*x^6 + 25*x^5 - 7*x^4 - 17*x^3 - 15*x^2 + 83*x + 3)/(x-1)^7.

Crossrefs

Cf. A172226, A201236, A201238, A201239, A201240, A201241, A201242.

Sequence in context: A284768 A024083 A172530 * A120436 A136742 A334285

Adjacent sequences: A201234 A201235 A201236 * A201238 A201239 A201240

Keyword

nonn

Author

Vaclav Kotesovec, Nov 28 2011

Status

approved