# A028283 (b-file synthesized from sequence entry)
0 1
1 4
2 10
3 32
4 110
5 392
6 1428
7 5280
8 19734
9 74360
10 281996
11 1074944
12 4115020
13 15808912
14 60917800
15 235350720
16 911315430
17 3535767000
18 13742347740
19 53495534400
20 208537056420
21 813950932080
22 3180614712600
23 12441628655040