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A168580 as a simple table

na(n)
12
21
32
41
52
61
72
85
94
107
118
127
138
1411
1514
1613
1716
1817
1916
2019
2120
2223
2328
2429
2528
2629
2728
2829
2940
3041
3144
3243
3350
3449
3552
3655
3756
3859
3962
4061
4168
4267
4368
4467
4576
4685
4786
4885
4986
5089
5188
5295
5398
54101
55104
56103
57106
58107
59106
60113
61124
62125
63124
64125
65136
66139
67146
68145
69146
70149

[2,1,2,1,2,1,2,5,4,7,8,7,8,11,14,13,16,17,16,19,
 20,23,28,29,28,29,28,29,40,41,44,43,50,49,52,55,
 56,59,62,61,68,67,68,67,76,85,86,85,86,89,88,95,
 98,101,104,103,106,107,106,113,124,125,124,125,
 136,139,146,145,146,149]