# A144047 (b-file synthesized from sequence entry)
0 1
1 4
2 22
3 111
4 570
5 2917
6 15112
7 78900
8 416525
9 2221529
10 11974498
11 65211746
12 358742016
13 1992975905
14 11178149883
15 63279615534
16 361464920864
17 2082869242399
18 12104344580384
19 70924864962233
20 418922049779244