3995136domain: NAppears in sequencesNumber of non-attacking placements of 3 rooks on an n X n board.at n=17A179058Number of minimum total dominating sets in the n X n rook complement graph.at n=17A303212a(n) = H(n-1, n, n+1) where H(a, b, c) = (a + b + c)*(a + b - c)*(b + c - a)*(c + a - b) is Heron's polynomial.at n=34A339488