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A107920 as a simple table

na(n)
00
11
21
3-1
4-3
5-1
65
77
8-3
9-17
10-11
1123
1245
13-1
14-91
15-89
1693
17271
1885
19-457
20-627
21287
221541
23967
24-2115
25-4049
26181
278279
287917
29-8641
30-24475
31-7193
3241757
3356143
34-27371
35-139657
36-84915
37194399
38364229
39-24569
40-753027
41-703889
42802165
432209943
44605613
45-3814273

[0,1,1,-1,-3,-1,5,7,-3,-17,-11,23,45,-1,-91,-89,
 93,271,85,-457,-627,287,1541,967,-2115,-4049,181,
 8279,7917,-8641,-24475,-7193,41757,56143,-27371,
 -139657,-84915,194399,364229,-24569,-753027,
 -703889,802165,2209943,605613,-3814273]