988181domain: NAppears in sequencesa(n) = Sum_{k=0..2n} (k+1) * A027023(n,2n-k).at n=12A027044Number of nX3 0..1 arrays with every element equal to 0, 2, 3, 4, 5, 6 or 7 king-move adjacent elements, with upper left element zero.at n=8A299716