(Translated by https://www.hiragana.jp/)
A211423 - OEIS
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A211423 as a simple table

na(n)
01
15
217
321
433
537
649
753
873
985
1097
11101
12121
13125
14137
15141
16161
17165
18193
19197
20209
21213
22225
23229
24257
25277
26289
27301
28313
29317
30337
31341
32377
33381
34393
35397
36433
37437
38449
39453
40481
41485
42497
43501
44513
45525
46537
47541
48569
49597
50641
51645
52657

[1,5,17,21,33,37,49,53,73,85,97,101,121,125,137,
 141,161,165,193,197,209,213,225,229,257,277,289,
 301,313,317,337,341,377,381,393,397,433,437,449,
 453,481,485,497,501,513,525,537,541,569,597,641,
 645,657]