# A158608 (b-file synthesized from sequence entry)
0 1
1 4
2 20
3 84
4 404
5 1748
6 8212
7 36180
8 167572
9 746452
10 3427604
11 15370836
12 70212500
13 316145876
14 1439545876
15 6497879892
16 29530613908
17 133496692180
18 605986514708
19 2741933589588
20 12437717824916
21 56308655258324
22 255312140456980