# A356913 (b-file synthesized from sequence entry) 0 1 1 0 2 0 3 0 4 4 5 10 6 40 7 210 8 784 9 5040 10 40200 11 369600 12 5285280 13 72072000 14 1006889520 15 14760345600 16 210510263040 17 3131345817600 18 49229619129600 19 818940523564800 20 15054020163619200 21 301204611031564800 22 6455999452413772800 23 146587705490513548800