# A162744 (b-file synthesized from sequence entry) 0 1 1 7 2 42 3 231 4 1260 5 6825 6 36960 7 200025 8 1082550 9 5858475 10 31704750 11 171577875 12 928536000 13 5024998125 14 27194002500 15 147166963125 16 796429856250 17 4310074059375 18 23325015131250 19 126228998109375 20 683118955312500