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A028981 as a simple table

na(n)
12
23
35
47
543
6211
7241
8251
9271
10281
11433
12443
13463
14827
15857
16877
17887
182111
192221
202441
212551
224003
234663
244993
258117
268447
278887
2820101
2920201
3021011
3121211
3221611
3321911
3422621
3522721
3622921
3723131
3823431
3923531
4023831
4124841

[2,3,5,7,43,211,241,251,271,281,433,443,463,827,
 857,877,887,2111,2221,2441,2551,4003,4663,4993,
 8117,8447,8887,20101,20201,21011,21211,21611,
 21911,22621,22721,22921,23131,23431,23531,23831,
 24841]