# A162937 (b-file synthesized from sequence entry)
0 1
1 6
2 30
3 150
4 735
5 3600
6 17640
7 86400
8 423210
9 2073000
10 10154040
11 49737000
12 243624060
13 1193330400
14 5845225440
15 28631349600
16 140243381160
17 686946520800
18 3364832751840
19 16481777119200
20 80731791755760
21 395444141299200