login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

A013206 as a simple table

na(n)
00
11
2-2
36
4-20
5120
6-872
77056
8-68000
9758400
10-9460352
11130918656
12-1995073280
1333173038080
14-597457144832
1511587651270656
16-240799724687360
175337660866396160
18-125711013390221312

[0,1,-2,6,-20,120,-872,7056,-68000,758400,
 -9460352,130918656,-1995073280,33173038080,
 -597457144832,11587651270656,-240799724687360,
 5337660866396160,-125711013390221312]