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A158895 as a simple table

na(n)
13
25
317
411
513
643
7257
819
941
10683
11241
122731
1329
14113
15331
1665537
1743691
1837
19109
20174763
2161681
225419
23397
242113
252796203
2697
27673
28251
294051
3053
31157
321613
3387211
3415790321
3559
363033169
3761
381321
39715827883

[3,5,17,11,13,43,257,19,41,683,241,2731,29,113,
 331,65537,43691,37,109,174763,61681,5419,397,2113,
 2796203,97,673,251,4051,53,157,1613,87211,
 15790321,59,3033169,61,1321,715827883]