# A348568 (b-file synthesized from sequence entry)
1 1
2 6
3 36
4 180
5 1260
6 7560
7 45360
8 83160
9 498960
10 1081080
11 6486480
12 32432400
13 110270160
14 551350800
15 2095133040
16 10475665200
17 73329656400
18 240940299600
19 1686582097200
20 48910880818800
21 1516237305382800