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A028920 as a simple table

na(n)
01
12
21
33
41
54
61
72
81
95
101
116
121
132
141
153
161
177
181
192
201
218
221
234
241
252
261
273
281
299
301
312
321
3310
341
355
361
372
381
393
401
4111
421
432
441
454
461
4712
481
492
501
513
521
536
541
552
561
5713
581
5914
601
612
621
633
641
654
661
672
681
695
701
717
721
732
741
753
761
7715
781
792
801
8116
821
834
841
852
861
873
881
898
901
912
921
936
941
955
961
972
981
993
1001
10117
1021

[1,2,1,3,1,4,1,2,1,5,1,6,1,2,1,3,1,7,1,2,1,8,1,4,
 1,2,1,3,1,9,1,2,1,10,1,5,1,2,1,3,1,11,1,2,1,4,1,
 12,1,2,1,3,1,6,1,2,1,13,1,14,1,2,1,3,1,4,1,2,1,5,
 1,7,1,2,1,3,1,15,1,2,1,16,1,4,1,2,1,3,1,8,1,2,1,6,
 1,5,1,2,1,3,1,17,1]