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A275308 as a simple table

na(n)
12
21
32
42
52
61
72
82
91
101
112
122
131
142
151
161
172
182
192
202
212
221
232
241
252
262
272
282
291
301
311
322
331
341
352
361
371
382
392
402
412
421
432
442
452
462
472
481
492
501

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