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A262663 as a simple table

na(n)
12
21
34
43
55
67
78
89
96
1010
1111
1212
1313
1414
1516
1617
1715
1818
1919
2020
2121
2222
2323
2424
2525
2626
2727
2829
2930
3031
3132
3228
3333
3434
3535
3637
3736
3838
3939
4040
4141
4242
4343
4444
4546
4647
4748
4849
4950
5045
5151
5252
5353
5454
5556
5657
5758
5855
5959
6060
6161
6262
6363
6464
6565
6667
6768

[2,1,4,3,5,7,8,9,6,10,11,12,13,14,16,17,15,18,19,
 20,21,22,23,24,25,26,27,29,30,31,32,28,33,34,35,
 37,36,38,39,40,41,42,43,44,46,47,48,49,50,45,51,
 52,53,54,56,57,58,55,59,60,61,62,63,64,65,67,68]