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A280773 as a simple table

na(n)
13
25
311
423
531
673
779
883
9109
10127
11139
12181
13191
14193
15197
16199
17211
18241
19227
20229
21233
22239
23251
24257
25271
26263
27269
28277
29281
30293

[3,5,11,23,31,73,79,83,109,127,139,181,191,193,
 197,199,211,241,227,229,233,239,251,257,271,263,
 269,277,281,293]