# A307570 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 15
4 58
5 215
6 789
7 2850
8 10219
9 36330
10 128383
11 450997
12 1576384
13 5484086
14 18997492
15 65547958
16 225329592
17 771920515
18 2635815051
19 8972752531
20 30456389557
21 103095375148
22 348071445217
23 1172252449310
24 3938655968745
25 13203699803684
26 44167916497886
27 147442143911193
28 491220771388477