# A046674 (b-file synthesized from sequence entry)
1 1
2 18
3 660
4 42000
5 4142880
6 586776960
7 113020427520
8 28432576972800
9 9056055981772800
10 3562946373482496000
11 1697172166720622592000
12 962691052768668647424000
13 641260394342965606809600000
14 495681727573700350908825600000
15 440084864982859007245221888000000