# A149138 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 9
4 36
5 109
6 451
7 1545
8 6616
9 24187
10 106547
11 405517
12 1824646
13 7147933
14 32650828
15 130817529
16 604062624
17 2464690317
18 11474497491
19 47519635981
20 222697034994
21 933589455107
22 4399682653158
23 18632396411535
24 88229438881360
25 376872306097157
26 1791926975472989
27 7711319584562603
28 36794160106977684