A182563 Number of ways to place n non-attacking semi-knights on an n x n chessboard.
1, 6, 70, 1289, 33864, 1148760, 47700972, 2344465830, 133055587660, 8559364525414, 615266768106190, 48861588247978827, 4247584874013608724, 401107335066453376830, 40880928693752664368224, 4472281486633326131737868
Offset: 1
Links
- V. Kotesovec, Non-attacking chess pieces, 6ed, p.289
Formula
Asymptotic: a(n) ~ n^(2n)/n!*exp(-3/2).
Extensions
a(16) from Vaclav Kotesovec, May 24 2021
Comments