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A248909 as a simple table

na(n)
11
21
31
41
51
61
77
81
91
101
111
121
1313
147
151
161
171
181
1919
201
217
221
231
241
251
2613
271
287
291
301
3131
321
331
341
357
361
3737
3819
3913
401
411
427
4343
441
451
461
471
481
4949
501
511
5213
531
541
551
567
5719
581
591
601
6161
6231
637
641
6513
661
6767
681
691
707
711
721
7373
7437
751
7619
777
7813
7979
801
811

[1,1,1,1,1,1,7,1,1,1,1,1,13,7,1,1,1,1,19,1,7,1,1,
 1,1,13,1,7,1,1,31,1,1,1,7,1,37,19,13,1,1,7,43,1,1,
 1,1,1,49,1,1,13,1,1,1,7,19,1,1,1,61,31,7,1,13,1,
 67,1,1,7,1,1,73,37,1,19,7,13,79,1,1]