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A127991 as a simple table

na(n)
11
21
31
41
51
611
71
83
921
1039
111
1231
131
141
151
167
17297
189
19351
201
211
2219
2391
241
25101
26141
2751
2833
2937
3049
311
32299
3337
341
353
3639
3721
381
3911
401
4119
421
4331
441071
45351
469
4743
481
49481
5011
51511
5283
533
543
5569
561
571
5891
591
6019
61187
6239
63219
64417
65553
6637
671
681
691
701369
71117
72693
73423
7431

[1,1,1,1,1,11,1,3,21,39,1,31,1,1,1,7,297,9,351,1,
 1,19,91,1,101,141,51,33,37,49,1,299,37,1,3,39,21,
 1,11,1,19,1,31,1071,351,9,43,1,481,11,511,83,3,3,
 69,1,1,91,1,19,187,39,219,417,553,37,1,1,1,1369,
 117,693,423,31]