# A319950 (b-file synthesized from sequence entry)
1 1
2 3
3 15
4 90
5 720
6 7200
7 79200
8 1029600
9 15444000
10 247104000
11 4447872000
12 88957440000
13 1868106240000
14 42966443520000
15 1074161088000000
16 27928188288000000
17 781989272064000000
18 23459678161920000000
19 727250023019520000000
20 23999250759644160000000