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A281681 as a simple table

na(n)
11
21
31
42
51
61
72
81
91
103
111
122
131
141
152
161
171
183
191
202
211
223
231
242
251
261
271
282
291
303
314
321
332
341
353
361
371
384
392
401
411
422
431
443
451
465
471
482
491
501
512
524
531
541
551
563
572
581
594
601
612
623
631
645
651
661
672
681
691
702
715
721
734
741
753
761
772
781
791
802
811
821
833
846
851
862
871
885
893
901
912
921
931
944
951
966
972
981
993
1001
1012
1021
1034
1043
1051
1061
1072
1081
1097
1101
1112
1121
1133
1141
1155
1161
1172
1181
1196
1201
1212
1221
1235
1241
1254
1261
1273
1282
1291

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