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A081768 as a simple table

na(n)
11
22
33
43
55
65
73
87
97
105
117
125
137
1411
159
163
175
1813
199
2013
217
223
2311
249
257
269
277
2811
2911
309
313
329
3323
3413
3519
369
373
387
3911
407
4111
429
439
449
457
467
475
4819
4913
5023
5115
527
5317
5413
559
567
575
585
597
6011
6111
6211
6319
6411
6515
669
6711
6821
6919
7011
719
729
739
7413
7511
765
7713
7821
799
8011
8115
827
8313
849
857
8611
877
8815

[1,2,3,3,5,5,3,7,7,5,7,5,7,11,9,3,5,13,9,13,7,3,
 11,9,7,9,7,11,11,9,3,9,23,13,19,9,3,7,11,7,11,9,9,
 9,7,7,5,19,13,23,15,7,17,13,9,7,5,5,7,11,11,11,19,
 11,15,9,11,21,19,11,9,9,9,13,11,5,13,21,9,11,15,7,
 13,9,7,11,7,15]