# A077639 (b-file synthesized from sequence entry)
1 1
2 2
3 4
4 6
5 14
6 40
7 56
8 100
9 2988
10 13200
11 805600
12 1323000
13 1744790520
14 112326337200
15 10154793943770044128560
16 26773964343922343708160
17 185027354760601080
18 1418008957437634586640