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A191591 as a simple table

na(n)
01
12
21
32
41
52
62
72
82
92
102
112
122
133
142
152
162
173
183
192
202
213
222
233
242
253
263
274
283
293
303
314
323
333
343
354
364
374
383
394
402
413
422
433
442
453
463
474
483
493
503
513
523
534
543
553
563
574
584
593
603
613
623
634
643
653
663
674
684
693
703
714
724
734
744
754
764
773
784
794
803
814
823
833
843
854
864
874
883
894
903
913
923
934
943
953
963
974
984
993
1002

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