# A261747 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 56 4 1712 5 92800 6 7918592 7 984237056 8 168662855680 9 38238313152512 10 11106033743298560 11 4026844843819663360 12 1784377436257886142464 13 949324216111786046259200 14 597340801661667138076672000 15 438858704839955952346364641280