# A331661 (b-file synthesized from sequence entry)
1 1
2 1
3 -3
4 6
5 30
6 -720
7 9180
8 -79020
9 -283500
10 41886720
11 -1580008680
12 44344341000
13 -851982076440
14 -5914076263200
15 1972181136416400
16 -153108297672649200
17 8900721288190544400
18 -403768420629168268800
19 9341444542413659205600
20 856476985107522346596000