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A257857 as a simple table

na(n)
12
21
31
40
52
60
71
81
91
101
112
120
132
140
152
161
171
181
191
201
211
220
232
240
252
260
272
280
291
301
311
321
331
341
351
361
372
380
392
400
412
420
432
440
452
461
471
481
491
501
511
521
531
541
551
560
572
580
592
600
612
620
632
640
652
660
671
681
691
701
711
721
731
741
751
761
771
781
792
800
812
820
832

[2,1,1,0,2,0,1,1,1,1,2,0,2,0,2,1,1,1,1,1,1,0,2,0,
 2,0,2,0,1,1,1,1,1,1,1,1,2,0,2,0,2,0,2,0,2,1,1,1,1,
 1,1,1,1,1,1,0,2,0,2,0,2,0,2,0,2,0,1,1,1,1,1,1,1,1,
 1,1,1,1,2,0,2,0,2]