# A145144 (b-file synthesized from sequence entry)
3 1
4 3
5 11
6 50
7 634
8 6804
9 71868
10 789984
11 11025936
12 174509280
13 2940903360
14 51707242080
15 987781034304
16 20520063789120
17 456583392034560
18 10712403843563520
19 265316096850923520
20 6948996535924162560