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A081520 as a simple table

na(n)
11
21
32
41
53
66
71
82
94
106
111
125
1310
1415
1520
161
172
183
194
206
218
221
237
2414
2521
2628
2735
2842
291
302
314
326
338
3410
3512
3614
371
383
396
409
4112
4215
4318
4421
4524
461
472
484
495
506
518
5210
5312
5414
5515
561
5711
5822
5933
6044
6155
6266
6377
6488
6599
66110
671
682
693
704
716
728
739
7410
7512
7614
7715
7816
791
8013
8126
8239
8352
8465
8578

[1,1,2,1,3,6,1,2,4,6,1,5,10,15,20,1,2,3,4,6,8,1,7,
 14,21,28,35,42,1,2,4,6,8,10,12,14,1,3,6,9,12,15,
 18,21,24,1,2,4,5,6,8,10,12,14,15,1,11,22,33,44,55,
 66,77,88,99,110,1,2,3,4,6,8,9,10,12,14,15,16,1,13,
 26,39,52,65,78]