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A031424 as a simple table

na(n)
12
21
34
42
51
61
76
83
92
101
111
121
138
144
151
162
171
181
191
201
2110
225
232
241
252
261
271
281
291
301
3112
326
334
343
352
362
371
381
391
401
411
421
4314
447
451
461
471
482
492
501
511
521
531
541
551
561
5716
588
591
604
611
621
631
642
651
661
671
681
691
701
711
721
7318
749
756
761
771
783
791
802
812
821
831
841
851
861
871
881
891
901
9120
9210
931
945
954
961

[2,1,4,2,1,1,6,3,2,1,1,1,8,4,1,2,1,1,1,1,10,5,2,1,
 2,1,1,1,1,1,12,6,4,3,2,2,1,1,1,1,1,1,14,7,1,1,1,2,
 2,1,1,1,1,1,1,1,16,8,1,4,1,1,1,2,1,1,1,1,1,1,1,1,
 18,9,6,1,1,3,1,2,2,1,1,1,1,1,1,1,1,1,20,10,1,5,4,
 1]