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A049581 as a simple table

na(n)
00
11
21
32
40
52
63
71
81
93
104
112
120
132
144
155
163
171
181
193
205
216
224
232
240
252
264
276
287
295
303
311
321
333
345
357
368
376
384
392
400
412
424
436
448
459
467
475
483
491
501
513
525
537
549
5510
568
576
584
592
600
612
624
636
648
6510
6611
679
687
695
703
711
721
733
745
757
769
7711
7812
7910
808
816
824
832
840
852
864
876
888
8910
9012

[0,1,1,2,0,2,3,1,1,3,4,2,0,2,4,5,3,1,1,3,5,6,4,2,
 0,2,4,6,7,5,3,1,1,3,5,7,8,6,4,2,0,2,4,6,8,9,7,5,3,
 1,1,3,5,7,9,10,8,6,4,2,0,2,4,6,8,10,11,9,7,5,3,1,
 1,3,5,7,9,11,12,10,8,6,4,2,0,2,4,6,8,10,12]