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A123948 as a simple table

na(n)
01
11
2-1
3-1
41
51
6-2
73
83
9-1
109
11-15
12-22
137
141
1596
16-184
17-314
18139
1919
20-1
21-2500
225250
2310575
24-5375
25-1026
2651
271
28-162000
29369900
30842310
31-498171
32-111179
337644
34141
35-1
3626471025
37-64790985
38-164634169
39109325076
4028870212
41-2322404
42-59193
43393
441

[1,1,-1,-1,1,1,-2,3,3,-1,9,-15,-22,7,1,96,-184,
 -314,139,19,-1,-2500,5250,10575,-5375,-1026,51,1,
 -162000,369900,842310,-498171,-111179,7644,141,-1,
 26471025,-64790985,-164634169,109325076,28870212,
 -2322404,-59193,393,1]