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A037881 as a simple table

na(n)
10
20
30
40
50
61
72
80
90
100
111
120
130
140
150
160
171
182
193
200
210
221
232
241
251
261
272
282
292
302
312
320
331
342
353
360
370
381
392
400
410
420
431
441
451
461
471
480
491
502
513
520
530
541
552
560
570
580
591
600
610
620
630
640
651
662
673
681
691
702
713
722
732
743
754
763
773
784
795
800
811
822
833
840
850
861
872
881
891
902

[0,0,0,0,0,1,2,0,0,0,1,0,0,0,0,0,1,2,3,0,0,1,2,1,
 1,1,2,2,2,2,2,0,1,2,3,0,0,1,2,0,0,0,1,1,1,1,1,0,1,
 2,3,0,0,1,2,0,0,0,1,0,0,0,0,0,1,2,3,1,1,2,3,2,2,3,
 4,3,3,4,5,0,1,2,3,0,0,1,2,1,1,2]