# A319788 (b-file synthesized from sequence entry)
1 1
2 4
3 20
4 120
5 560
6 19600
7 27720
8 1521520
9 7207200
10 2845642800
11 4170866700
12 249466897680
13 9117204216120
14 1723262134513920
15 2525472914524560
16 189169152233901840
17 1782424363173854400
18 28708458878287188000
19 15137401000857582807360
20 32632841312905676442600
21 647550654467707884653760