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A271498 as a simple table

na(n)
11
21
31
41
51
61
77
81
91
101
117
121
137
147
151
161
171
181
197
201
217
227
231
241
257
267
271
287
291
301
3131
327
337
341
357
361
377
387
397
401
417
427
437
447
451
467
4731
481
497
507
511
527
537
541
5531
567
577
587
5931
601
6131
6231
637
647
657
667
677
687
691
707
711
721
737
747
757
767
771
787
7931
807
811
827
831
847
851
861
871
887
891
901
9131
921
9331
9431
957
967
977
987

[1,1,1,1,1,1,7,1,1,1,7,1,7,7,1,1,1,1,7,1,7,7,1,1,
 7,7,1,7,1,1,31,7,7,1,7,1,7,7,7,1,7,7,7,7,1,7,31,1,
 7,7,1,7,7,1,31,7,7,7,31,1,31,31,7,7,7,7,7,7,1,7,1,
 1,7,7,7,7,1,7,31,7,1,7,1,7,1,1,1,7,1,1,31,1,31,31,
 7,7,7,7]