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A291568 as a simple table

na(n)
11
21
31
41
5-3
61
71
81
91
10-3
111
121
131
141
15-3
161
171
181
191
20-3
211
221
231
241
25-3
261
271
281
291
30-3
311
321
331
341
35-3
361
371
381
391
40-3
411
421
431
441
45-3
461
471
481
491
50-3
511
521
531
541
55-3
561
571
581
591
60-3
611
621
631
641
65-3
661
671
681
691
70-3

[1,1,1,1,-3,1,1,1,1,-3,1,1,1,1,-3,1,1,1,1,-3,1,1,
 1,1,-3,1,1,1,1,-3,1,1,1,1,-3,1,1,1,1,-3,1,1,1,1,
 -3,1,1,1,1,-3,1,1,1,1,-3,1,1,1,1,-3,1,1,1,1,-3,1,
 1,1,1,-3]