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A000034 as a simple table

na(n)
01
12
21
32
41
52
61
72
81
92
101
112
121
132
141
152
161
172
181
192
201
212
221
232
241
252
261
272
281
292
301
312
321
332
341
352
361
372
381
392
401
412
421
432
441
452
461
472
481
492
501
512
521
532
541
552
561
572
581
592
601
612
621
632
641
652
661
672
681
692
701
712
721
732
741
752
761
772
781
792
801
812
821
832
841
852
861
872
881
892
901
912
921
932
941
952
961
972
981
992
1001
1012

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