# A054993 (b-file synthesized from sequence entry)
0 1
1 2
2 8
3 42
4 260
5 1796
6 13396
7 105706
8 870772
9 7420836
10 65004584
11 582521748
12 5320936416
13 49402687392
14 465189744448
15 4434492302426
16 42731740126228
17 415736458808868
18 4079436831493480
19 40338413922226212
20 401652846850965808
21 4024556509468827432
22 40558226664529024000
23 410887438338905738908
24 4182776248940752113344
25 42770152711524569532616
26 439143340987014152920384
27 4526179842103708969039296