# A171989 (b-file synthesized from sequence entry)
1 2
2 6
3 30
4 210
5 2310
6 29464
7 476928
8 9671392
9 222388792
10 6438663000
11 200560490130
12 7379606916000
13 299261862900000
14 13004421443456272
15 614231422273479360
16 31727029501157817600
17 1915248189055217892480
18 116762424492324428512272