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A049290 as a simple table

na(n)
11
21
31
41
53
61
71
87
913
101
111
1215
1397
1471
151
161
1731
18625
192143
20461
211
221
2363
243841
2554335
2668641
273447
281
291
30127
3123233
321321471
338563601
343011263
3529093
361
371
38255
39139777
4031817471
411035045121
422228419359
43173773153
44273343
451
461
47511
48839425

[1,1,1,1,3,1,1,7,13,1,1,15,97,71,1,1,31,625,2143,
 461,1,1,63,3841,54335,68641,3447,1,1,127,23233,
 1321471,8563601,3011263,29093,1,1,255,139777,
 31817471,1035045121,2228419359,173773153,273343,1,
 1,511,839425]