# A028576 (b-file synthesized from sequence entry)
1 1
2 4
3 33
4 304
5 3175
6 35556
7 420665
8 5176000
9 65664000
10 853367900
11 11309870605
12 152342891952
13 2080240006923
14 28738242567524
15 401024083514775
16 5645275548076800
17 80084088088568947
18 1143862232096407392
19 16437995698573558421
20 237520818846111947600