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A131406 as a simple table

na(n)
11
22
31
41
52
61
72
81
92
101
111
122
131
142
151
162
171
182
191
202
211
221
232
241
252
261
272
281
292
301
312
321
332
341
352
361
371
382
391
402
411
422
431
442
451
462
471
482
491
502
511
522
531
542
551

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