242220

Appears in sequences

• Number of ways to place 3 nonattacking semi-queens on an n X n board.at n=11A202654
• Table read by rows, T(n, k) = Y(2*n, k, Z(2*n - k)) where Y are the partial Bell polynomials and Z(m) is the list [A126869(j), j=-1..2*m].at n=24A350463