17893715840domain: NAppears in sequencesa(n) = Product_{k=1..n} (9*k - 1); 9-factorial numbers.at n=7A049211Triangle sequence: T(n, k) = -Product_{j=0..k+1} ((n+1)*j - 1).at n=42A153187Triangle read by rows: T(n,k) = Product_{i=0..k-2} (i*n + n - 1).at n=34A153273