# A057973 (b-file synthesized from sequence entry)
1 1
2 2
3 5
4 16
5 55
6 225
7 949
8 4269
9 19500
10 91115
11 429742
12 2047660
13 9820197
14 47383255
15 229725560
16 1118568692
17 5466616025
18 26804560282
19 131817042605
20 649952289243