# A109021 (b-file synthesized from sequence entry)
0 0
1 0
2 8
3 88
4 720
5 5360
6 38488
7 272328
8 1915040
9 13431520
10 94099368
11 658931768
12 4613230960
13 32294742480
14 226069574648
15 1582506154408
16 11077600476480
17 77543375522240
18 542804145216328
19 3799630566196248
20 26597418612419600
21 186181944234074800
22 1303273651479936408