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A011620 as a simple table

na(n)
00
11
21
31
41
51
61
7-1
81
91
101
11-1
121
131
14-1
151
161
171
181
19-1
201
21-1
22-1
231
241
251
261
271
28-1
29-1
301
31-1
321
33-1
341
35-1
361
37-1
38-1
391
401
41-1
42-1
431
44-1
451
461
47-1
481
491
501
511
521
53-1
541
55-1
56-1
57-1
58-1
591
601
61-1
62-1
63-1
641
651
66-1
671
681
691
70-1
71-1
721
73-1
74-1
751
76-1
771
781
791
801

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