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A121891 as a simple table

na(n)
13
24
32
43
53
62
75
84
92
105
115
122
133
144
152
165
173
182
197
203
212
225
2310
242
253
264
272
283
293
302
315
324
332
3411
357
362
373
384
392
407
413
422
4313
443
452
4611
475
482
493
504
512
523
533
542
556
564
572
587
5919
602
613
624
632
6410
653
662
675
683
692
705
715
722
733
744
752
763
773
782
796
804
812
825
837
842
853
864
872
887
893
902
915
923
932
9411
9513
962
973
984
992
1003
1013

[3,4,2,3,3,2,5,4,2,5,5,2,3,4,2,5,3,2,7,3,2,5,10,2,
 3,4,2,3,3,2,5,4,2,11,7,2,3,4,2,7,3,2,13,3,2,11,5,
 2,3,4,2,3,3,2,6,4,2,7,19,2,3,4,2,10,3,2,5,3,2,5,5,
 2,3,4,2,3,3,2,6,4,2,5,7,2,3,4,2,7,3,2,5,3,2,11,13,
 2,3,4,2,3,3]