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A073407 as a simple table

na(n)
11
21
32
41
53
61
73
81
93
102
114
121
134
142
154
161
175
181
194
202
214
223
235
241
255
263
274
282
295
303
315
321
335
344
355
361
375
383
395
402
416
423
435
443
455
464
476
481
495
504
516
523
536
541
556
562
575
584
596
603
616
624
635
641
656
664
676
684
696
704
716
721
736
744
756
763
776
784
796
802
815
825
837
843
857
864
876
883
897
904
916
924
936
945
956
961
977
984
996
1004
1017
1025
1037
1043
1056

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