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A080891 as a simple table

na(n)
00
11
2-1
3-1
41
50
61
7-1
8-1
91
100
111
12-1
13-1
141
150
161
17-1
18-1
191
200
211
22-1
23-1
241
250
261
27-1
28-1
291
300
311
32-1
33-1
341
350
361
37-1
38-1
391
400
411
42-1
43-1
441
450
461
47-1
48-1
491
500
511
52-1
53-1
541
550
561
57-1
58-1
591
600
611
62-1
63-1
641
650
661
67-1
68-1
691
700
711
72-1
73-1
741
750
761
77-1
78-1
791
800
811
82-1
83-1
841
850
861
87-1
88-1
891
900
911
92-1
93-1
941
950
961
97-1
98-1
991
1000

[0,1,-1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,
 0,1,-1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0,
 1,-1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0,1,
 -1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0,1,
 -1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0,1,-1,-1,1,0]