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A080681 as a simple table

na(n)
11
22
33
44
55
66
77
88
99
1010
1111
1212
1313
1414
1515
1616
1717
1818
1920
2021
2122
2224
2325
2426
2527
2628
2730
2832
2933
3034
3135
3236
3339
3440
3542
3644
3745
3848
3949
4050
4151
4252
4354
4455
4556
4660
4763
4864
4965
5066
5168
5270
5372
5475
5577
5678
5780
5881
5984
6085
6188
6290
6391
6496
6598
6699
67100
68102
69104
70105

[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,20,
 21,22,24,25,26,27,28,30,32,33,34,35,36,39,40,42,
 44,45,48,49,50,51,52,54,55,56,60,63,64,65,66,68,
 70,72,75,77,78,80,81,84,85,88,90,91,96,98,99,100,
 102,104,105]