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A138749 as a simple table

na(n)
1-1
2-7
3-9
417
579
673
7-249
8-863
9-481
103353
119111
121457
13-42641
14-92567
1528071
16518977
17897599
18-799687
19-6087369
20-8176303
2114084239
2269049993
2367678791
24-209892383
25-758178721
26-466895527
272857102551
288048682737
291811852719
30-36619708247

[-1,-7,-9,17,79,73,-249,-863,-481,3353,9111,1457,
 -42641,-92567,28071,518977,897599,-799687,
 -6087369,-8176303,14084239,69049993,67678791,
 -209892383,-758178721,-466895527,2857102551,
 8048682737,1811852719,-36619708247]