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A220947 as a simple table

na(n)
12
23
32
411
53
62
75
83
92
1011
115
1241
13181
1431
1573
1689
175
187
1971
2011
2129
225
23193
2441
2589
2661
272
2843
293
3031
3113
32191
332
3461
35103
3697
37103
3847
39383
40367
4189
4217
43191
441627
45193
46163
475
48337
49349
5023
51149
52193
53199
54233
55173
56617
57593
5859
59113
60151

[2,3,2,11,3,2,5,3,2,11,5,41,181,31,73,89,5,7,71,
 11,29,5,193,41,89,61,2,43,3,31,13,191,2,61,103,97,
 103,47,383,367,89,17,191,1627,193,163,5,337,349,
 23,149,193,199,233,173,617,593,59,113,151]