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A181432 as a simple table

na(n)
11
2-1
3-1
4-1
51
6-1
71
81
91
101
11-1
12-1
131
14-1
15-1
161
171
18-1
19-1
201
211
22-1
23-1
241
251
261
27-1
28-1
29-1
301
31-1
32-1
33-1
34-1
351
36-1
371
381
391
401
411
421
431
441
451
461
47-1
481
49-1
50-1
51-1
52-1
531
54-1
551
56-1
57-1
58-1
59-1
601
611
621
63-1
64-1
65-1
66-1
67-1
681
69-1
701
711
72-1
73-1
741
751
76-1
771
78-1
79-1
801
811
821
83-1

[1,-1,-1,-1,1,-1,1,1,1,1,-1,-1,1,-1,-1,1,1,-1,-1,
 1,1,-1,-1,1,1,1,-1,-1,-1,1,-1,-1,-1,-1,1,-1,1,1,1,
 1,1,1,1,1,1,1,-1,1,-1,-1,-1,-1,1,-1,1,-1,-1,-1,-1,
 1,1,1,-1,-1,-1,-1,-1,1,-1,1,1,-1,-1,1,1,-1,1,-1,
 -1,1,1,1,-1]