# A051440 (b-file synthesized from sequence entry)
0 3
1 4
2 8
3 20
4 54
5 132
6 312
7 720
8 1620
9 3672
10 8162
11 17864
12 38874
13 84018
14 180504
15 386094
16 821642
17 1742538
18 3681132
19 7754078
20 16290048
21 34136030
22 71378570
23 148948140
24 310248242
25 645155198
26 1339484198
27 2777105130
28 5750079048