# A365975 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 6
4 30
5 180
6 1260
7 10800
8 104760
9 1130760
10 13776480
11 184044960
12 2670220080
13 42222280320
14 718144004160
15 13061603808000
16 254036916144000
17 5247117638294400
18 114652672773408000
19 2647321293055507200
20 64330669872690566400
21 1640738743703289331200