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A028281 as a simple table

na(n)
01
15
27
323
49
531
655
711
861
913
1073
11237
12735
1315
141045
151947
16115
171441
184587
1917
20131
21611
221937
234433
247579
259867
2619
27185
2821
29205
301241
316477
327923
3328101
34271
359595
36105621
3725
38295
392191
4011515
4145619
42141645
43353685
441076559
4527
461571889

[1,5,7,23,9,31,55,11,61,13,73,237,735,15,1045,
 1947,115,1441,4587,17,131,611,1937,4433,7579,9867,
 19,185,21,205,1241,6477,7923,28101,271,9595,
 105621,25,295,2191,11515,45619,141645,353685,
 1076559,27,1571889]