# A018211 (b-file synthesized from sequence entry)
0 1
1 4
2 20
3 60
4 170
5 396
6 868
7 1716
8 3235
9 5720
10 9752
11 15912
12 25236
13 38760
14 58200
15 85272
16 122661
17 173052
18 240460
19 328900
20 444158
21 592020
22 780572
23 1017900
24 1315015
25 1682928
26 2136304
27 2689808
28 3362600
29 4173840
30 5148144
31 6310128