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A173261 as a simple table

na(n)
21
31
42
51
63
71
81
94
101
112
121
135
141
153
161
171
186
191
204
211
222
231
247
251
265
271
283
291
301
318
321
336
341
354
361
372
381
399
401
417
421
435
441
453
461
471
4810
491
508
511
526
531
544
551
562
571
5811
591
609
611
627
631
645
651
663
671
681
6912
701
7110
721
738
741
756
761
774
781
792
801
8113
821
8311
841
859
861
877
881
895
901
913
921
931
9414
951
9612
971
9810
991
1008
1011
1026
1031
1044
1051
1062

[1,1,2,1,3,1,1,4,1,2,1,5,1,3,1,1,6,1,4,1,2,1,7,1,
 5,1,3,1,1,8,1,6,1,4,1,2,1,9,1,7,1,5,1,3,1,1,10,1,
 8,1,6,1,4,1,2,1,11,1,9,1,7,1,5,1,3,1,1,12,1,10,1,
 8,1,6,1,4,1,2,1,13,1,11,1,9,1,7,1,5,1,3,1,1,14,1,
 12,1,10,1,8,1,6,1,4,1,2]