257860425672domain: NAppears in sequencesNumber of ways to place n^2 nonattacking kings on a 2n X 2n cylindrical chessboard.at n=10A137432Number of ways to place 10n nonattacking kings on a 20 X 2n cylindrical chessboard.at n=9A195654Number of ways to place 10n nonattacking kings on a vertical cylinder 20 X 2n.at n=9A195659