# A054768 (b-file synthesized from sequence entry)
0 -2
1 1
2 1
3 9
4 72
5 792
6 10512
7 165168
8 2992608
9 61445088
10 1409857920
11 35751525120
12 992877886080
13 29970166769280
14 976990865518080
15 34206887786803200
16 1280236466132467200
17 51004766655793036800
18 2155155171665039308800