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A199898 as a simple table

na(n)
11
21
33
41
55
67
71
87
915
1015
111
129
1325
1449
1533
161
1711
1837
19111
20159
2175
221
2313
2451
25209
26461
27533
28171
291
3015
3167
32351
331043
342035
351783
36391
371
3817
3985
40545
412031
425725
438823
446027
45899
461
4719
48105
49799
503573
5113363
5230199
5339053
5420437
552077
561
5721
58127
591121
605839

[1,1,3,1,5,7,1,7,15,15,1,9,25,49,33,1,11,37,111,
 159,75,1,13,51,209,461,533,171,1,15,67,351,1043,
 2035,1783,391,1,17,85,545,2031,5725,8823,6027,899,
 1,19,105,799,3573,13363,30199,39053,20437,2077,1,
 21,127,1121,5839]