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A168508 as a simple table

na(n)
11
21
31
42
51
61
72
81
91
101
113
121
131
141
151
163
172
181
191
201
211
224
232
241
251
261
271
281
294
302
311
321
331
341
351
361
375
382
392
401
411
421
431
441
451
465
473
482
491
501
511
521
531
541
551
566
573
582
591
601
611
621
631
641
651
661
676
683
692
702
711
721
731
741
751
761
771
781
797
803
812
822
831
841
851
861
871
881
891
901
911
927
934
942
952
961
971
981
991
1001
1011
1021
1031
1041
1051

[1,1,1,2,1,1,2,1,1,1,3,1,1,1,1,3,2,1,1,1,1,4,2,1,
 1,1,1,1,4,2,1,1,1,1,1,1,5,2,2,1,1,1,1,1,1,5,3,2,1,
 1,1,1,1,1,1,6,3,2,1,1,1,1,1,1,1,1,6,3,2,2,1,1,1,1,
 1,1,1,1,7,3,2,2,1,1,1,1,1,1,1,1,1,7,4,2,2,1,1,1,1,
 1,1,1,1,1,1]