# A019580 (b-file synthesized from sequence entry)
4 1
5 20
6 375
7 7560
8 167825
9 4110120
10 110602800
11 3252075750
12 103881924300
13 3585467886000
14 133052005386300
15 5284678706307000
16 223761183682286250
17 10063370411081988000
18 479152851159102120000
19 24082014064135799772000