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A178781 as a simple table

na(n)
0-1
11
20
31
40
50
60
7-1
8-1
90
10-1
110
121
130
142
150
161
170
180
19-1
200
21-2
220
23-1
240
251
260
271
281
290
300
310
32-1
330
34-1
351

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