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A280521 as a simple table

na(n)
11
21
32
41
52
62
71
82
92
103
112
121
132
142
153
162
173
183
192
201
212
222
233
242
253
263
272
283
293
304
313
322
331
342
352
363
372
383
393
402
413
423
434
443
452
463
473
484
493
504
514
523
532
541
552
562
573
582
593
603
612
623
633
644
653
662
673
683
694
703
714
724
733
742
753
763
774
783
794
804
813
824
834
845
854
863
872

[1,1,2,1,2,2,1,2,2,3,2,1,2,2,3,2,3,3,2,1,2,2,3,2,
 3,3,2,3,3,4,3,2,1,2,2,3,2,3,3,2,3,3,4,3,2,3,3,4,3,
 4,4,3,2,1,2,2,3,2,3,3,2,3,3,4,3,2,3,3,4,3,4,4,3,2,
 3,3,4,3,4,4,3,4,4,5,4,3,2]