A201511 Number of ways to place n nonattacking wazirs on an n X n board.

1, 1, 2, 22, 405, 10741, 368868, 15516804, 771464278, 44218721793, 2868879752822, 207739939478618, 16602826428818482, 1451305771147909684, 137715836041691050398, 14096224186664736126206, 1547966111897855935957132, 181519663430661533452513680, 22636566614411901986006002896

Offset: 0

Author

Vaclav Kotesovec, Dec 02 2011

Keywords

• nonn
• nice
• hard

Comments

Wazir is a leaper [0,1].

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 0..21 (terms a(11)-a(18) computed by Peter Tittmann)
• V. Kotesovec, Non-attacking chess pieces, 6ed, 2013, p. 382.
• Peter Tittmann, Polynomials of nxn Grid Graphs [broken link]

Crossrefs

Cf. A172225, A172226, A172227, A172228, A178409, A201507, A201508, A201510.

Cf. A006506.

Main diagonal of A232833.

Formula

Asymptotics (Vaclav Kotesovec, Nov 29 2011): a(n) ~ n^(2n)/n!*exp(-5/2).

Extensions

a(19)-a(20) from Vaclav Kotesovec, Aug 30 2016

a(0)=1 prepended by Alois P. Heinz, Apr 16 2024