# A000648 (b-file synthesized from sequence entry)
0 1
1 3
2 18
3 61
4 225
5 716
6 2272
7 6826
8 20238
9 58552
10 167625
11 473929
12 1330490
13 3709591
14 10296336
15 28466065
16 78481065
17 215878221
18 592832960
19 1625887129
20 4454936029
21 12198071235
22 33383810793
23 91336813784
24 249851178964
25 683421422654