409080

Appears in sequences

• Triangle read by rows: T(n,k) is the number of deco polyominoes of height n with k cells in the first column. (A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column).at n=49A100822
• Array read by antidiagonals: T(m,n) = Sum( n <= i <= m+n-1 ) i!.at n=40A211370
• Column 2 of triangle A354650: a(n) = A354650(n,2), for n >= 1.at n=9A354655