# A000476 (b-file synthesized from sequence entry)
5 15
6 72
7 609
8 4960
9 46188
10 471660
11 5275941
12 64146768
13 842803767
14 11902900380
15 179857257960
16 2895705788736
17 49491631601635
18 895010868095256
19 17074867330880805
20 342733960299356800
21 7220616209235766260
22 159312370008282356844
23 3673720238903201471593