# A001577 (b-file synthesized from sequence entry)
1 1
2 1
3 2
4 6
5 60
6 2880
7 2246400
8 135862272000
9 10376834265907200000
10 77540115374348238323712000000000
11 71611262431705169979126571320506685849600000000000000
12 799595359352229378487949660335170674324575940302246074414582988800000000000000000000000