login

A020547 as a simple table

na(n)
00
10
22
330
4552
514280
6517680
725396560
81625662080
9131681531520
1013168185811200
111593350882323200
12229442532323558400
1338775788037405619200
147600054456464819148800
151710012252722891749632000
16437763136697374129754112000

[0,0,2,30,552,14280,517680,25396560,1625662080,
 131681531520,13168185811200,1593350882323200,
 229442532323558400,38775788037405619200,
 7600054456464819148800,1710012252722891749632000,
 437763136697374129754112000]