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A287920 as a simple table

na(n)
11
21
31
42
51
61
73
82
91
101
115
123
132
141
151
166
174
182
191
201
211
228
235
243
252
261
271
281
299
306
313
322
331
341
351
361
3711
387
394
403
412
421
431
441
451
4614
479
485
494
502
512
521
531
541
551
5615
5710
586
594
602
612
621
631
641
651
661
6718
6812
697
705
713
722
732
741
751
761
771
781
7920
8013
818
825
833
843
852
862
871
881
891
901
911

[1,1,1,2,1,1,3,2,1,1,5,3,2,1,1,6,4,2,1,1,1,8,5,3,
 2,1,1,1,9,6,3,2,1,1,1,1,11,7,4,3,2,1,1,1,1,14,9,5,
 4,2,2,1,1,1,1,15,10,6,4,2,2,1,1,1,1,1,18,12,7,5,3,
 2,2,1,1,1,1,1,20,13,8,5,3,3,2,2,1,1,1,1,1]