A195654 Number of ways to place 10n nonattacking kings on a 20 X 2n cylindrical chessboard.

11264, 48132, 251126, 1473764, 9434784, 64923594, 476033636, 3694894500, 30179587994, 257860425672, 2290966142762, 21042965606234, 198765197377402, 1921681775292272, 18940490557328616, 189679152583318596, 1924757095250611458, 19746535064318923758

Offset

1,1

Comments

This cylinder is horizontal: a chessboard where it is supposed that rows 1 and 2n are in contact (number of columns = 20, number of rows = 2n).

Links

Alex V. Breger, Table of n, a(n) for n = 1..500

Artem M. Karavaev, Zealint blog (in Russian)

V. Kotesovec, Non-attacking chess pieces

Vaclav Kotesovec, Generating function

Formula

Recurrence order is 916.

Crossrefs

Cf. A137432, A195653, A195649, A195659.

Sequence in context: A051520 A051346 A217125 * A195649 A110375 A252859

Adjacent sequences: A195651 A195652 A195653 * A195655 A195656 A195657

Keyword

nonn

Author

Vaclav Kotesovec, Sep 22 2011

Status

approved