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A305053 as a simple table

na(n)
10
2-1
30
4-1
50
6-1
70
8-1
91
10-1
110
12-1
131
14-1
150
16-1
170
180
190
20-1
210
22-1
230
24-1
251
260
272
28-1
291
30-1
310
32-1
330
34-1
350
360
371
38-1
391
40-1
410
42-1
431
44-1
451
46-1
471
48-1
491
500
510
520
530
541
550
56-1
570
580
590
60-1
611
62-1
631
64-1
651
66-1
670
68-1
690
70-1
711
720
731
740
751
76-1
770

[0,-1,0,-1,0,-1,0,-1,1,-1,0,-1,1,-1,0,-1,0,0,0,-1,
 0,-1,0,-1,1,0,2,-1,1,-1,0,-1,0,-1,0,0,1,-1,1,-1,0,
 -1,1,-1,1,-1,1,-1,1,0,0,0,0,1,0,-1,0,0,0,-1,1,-1,
 1,-1,1,-1,0,-1,0,-1,1,0,1,0,1,-1,0]