# A056569 (b-file synthesized from sequence entry)
0 1
1 2
2 3
3 6
4 14
5 42
6 158
7 756
8 4594
9 35532
10 349428
11 4370436
12 69532964
13 1407280392
14 36228710348
15 1186337370456
16 49415178236344
17 2618246576596392
18 176462813970065208
19 15128228719573952976
20 1649746715671916095304