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A111521 as a simple table

na(n)
01
13
23
3-3
4-8
5-1
6-44
7-151
8259
9-49
10-5250
1117176
1218870
13-443793
141765849
151813152
16-60621125
17321255514
18-62856104
19-11540412088
2088870982824
21-195655026297
22-2574468817607
2332370146955580
24-155239071570949
25-402613805424503
2613621655040570928

[1,3,3,-3,-8,-1,-44,-151,259,-49,-5250,17176,
 18870,-443793,1765849,1813152,-60621125,321255514,
 -62856104,-11540412088,88870982824,-195655026297,
 -2574468817607,32370146955580,-155239071570949,
 -402613805424503,13621655040570928]