# A051858 (b-file synthesized from sequence entry)
1 4
2 12
3 60
4 180
5 420
6 5100
7 60900
8 135720
9 161880
10 163020
11 218460
12 595140
13 1108560
14 2574180
15 2740140
16 3248700
17 3535140
18 3723720
19 3729180
20 8197200
21 13933920
22 20218440
23 23605320
24 28569240
25 33874680
26 47248920
27 68667480
28 69372420