# A327927 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 6
4 30
5 150
6 1020
7 7140
8 63420
9 611100
10 6625080
11 72875880
12 977213160
13 12876743880
14 190951160400
15 2975661889200
16 51767677962000
17 886225654314000
18 17136230971860000
19 329530590793404000
20 7035395004749311200
21 151961029211943151200