628488domain: NAppears in sequencesNumber of ways to place a non-attacking white and black queen on n X n chessboard.at n=28A035291Number of n X 4 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 0 1 vertically.at n=27A207064a(n) = Sum_{k=0..n} (k+1) * 8^k * binomial(2*n+2,n-k).at n=5A386986