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A013293 as a simple table

na(n)
01
10
20
30
4-3
540
6-250
71008
8-5887
956880
10-263724
11-1848000
1236228093
13-377490984
147141572490
15-132772794000
161495810787297
17-10978685025568
18115616765332680
19-1113424428155904
20-36631866029794659

[1,0,0,0,-3,40,-250,1008,-5887,56880,-263724,
 -1848000,36228093,-377490984,7141572490,
 -132772794000,1495810787297,-10978685025568,
 115616765332680,-1113424428155904,
 -36631866029794659]