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A030640 as a simple table

na(n)
01
11
2-3
3-2
45
53
6-7
7-4
89
95
10-11
11-6
1213
137
14-15
15-8
1617
179
18-19
19-10
2021
2111
22-23
23-12
2425
2513
26-27
27-14
2829
2915
30-31
31-16
3233
3317
34-35
35-18
3637
3719
38-39
39-20
4041
4121
42-43
43-22
4445
4523
46-47
47-24
4849
4925
50-51
51-26
5253
5327
54-55
55-28
5657
5729
58-59

[1,1,-3,-2,5,3,-7,-4,9,5,-11,-6,13,7,-15,-8,17,9,
 -19,-10,21,11,-23,-12,25,13,-27,-14,29,15,-31,-16,
 33,17,-35,-18,37,19,-39,-20,41,21,-43,-22,45,23,
 -47,-24,49,25,-51,-26,53,27,-55,-28,57,29,-59]