# A356661 (b-file synthesized from sequence entry)
1 1
2 4
3 12
4 60
5 240
6 1860
7 10080
8 95760
9 766080
10 8210160
11 79833600
12 1100484000
13 12454041600
14 188172784800
15 2683799838720
16 44951306400000
17 711374856192000
18 13745322470880000
19 243290200817664000
20 5142812718440517120
21 103294640229580800000
22 2351280996859354560000