# A356298 (b-file synthesized from sequence entry)
1 1
2 7
3 41
4 290
5 2074
6 18444
7 165108
8 1749264
9 19412496
10 241299360
11 3097006560
12 45546606720
13 673536159360
14 10986261431040
15 187460277177600
16 3445281394329600
17 64637392771123200
18 1325310849663897600
19 27498565425087590400
20 616389533324974080000