A190393 Number of ways to place n nonattacking nightriders on an n X n toroidal board.

1, 2, 6, 24, 120, 144, 28, 1408, 2025, 86400, 1782, 1092096, 4186, 31360, 241920000, 23953408, 140692, 114108912, 1092690

Offset: 1

Author

Vaclav Kotesovec, May 10 2011

Keywords

• nonn
• nice
• hard
• more

Comments

A nightrider is a fairy chess piece that can move (proportionate to how a knight moves) in any direction.

Links

• Vaclav Kotesovec, Number of ways of placing non-attacking queens, kings, bishops and knights (in English and Czech).

Crossrefs

Cf. A172141, A173429, A051906.

Extensions

Terms a(16)-a(17) from Vaclav Kotesovec, May 14 2011

Terms a(18)-a(19) from Vaclav Kotesovec, May 28 2011