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A001876 as a simple table

na(n)
00
11
21
31
41
51
62
71
81
91
101
112
122
131
141
151
162
171
182
191
201
212
222
231
242
251
262
271
281
291
302
312
322
332
341
351
363
371
381
391
401
412
423
431
442
451
462
471
483
491
501
512
522
531
542
552
562
571
581
591
602
612
622
632
642
651
664
671
681
691
701
712
723
731
741
751
762
772
783
791
802
812
822
831
843
851
862
871

[0,1,1,1,1,1,2,1,1,1,1,2,2,1,1,1,2,1,2,1,1,2,2,1,
 2,1,2,1,1,1,2,2,2,2,1,1,3,1,1,1,1,2,3,1,2,1,2,1,3,
 1,1,2,2,1,2,2,2,1,1,1,2,2,2,2,2,1,4,1,1,1,1,2,3,1,
 1,1,2,2,3,1,2,2,2,1,3,1,2,1]