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A030018 as a simple table

na(n)
01
1-2
21
3-1
42
5-3
67
7-10
813
9-21
1026
11-33
1253
13-80
14127
15-193
16254
17-355
18527
19-764
201149
21-1699
222436
23-3563
245133
25-7352
2610819
27-15863
2823162
29-33887
3048969
31-70936
32103571
33-150715
34219844
35-320973
36466641
37-679232
38988627
39-1437185
402094446
41-3052743

[1,-2,1,-1,2,-3,7,-10,13,-21,26,-33,53,-80,127,
 -193,254,-355,527,-764,1149,-1699,2436,-3563,5133,
 -7352,10819,-15863,23162,-33887,48969,-70936,
 103571,-150715,219844,-320973,466641,-679232,
 988627,-1437185,2094446,-3052743]