75530domain: NAppears in sequencesRow sums of triangle A132921.at n=22A132922Number of ways to place 3 non-attacking ferses on an n X n board.at n=8A201244Smallest m, such that there are exactly n solutions of the equation (m+k)' = m' + k', where 1 <= k <= 2*m and x' = A003415(x), the arithmetic derivative of x.at n=18A258138