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A018431 as a simple table

na(n)
11
22
33
44
56
69
711
812
918
1022
1133
1236
1344
1466
1599
16132
17198
18396

[1,2,3,4,6,9,11,12,18,22,33,36,44,66,99,132,198,
 396]