login

A171521 as a simple table

na(n)
11
22
33
45
56
67
78
89
910
1011
1113
1214
1315
1416
1517
1618
1719
1820
1921
2022
2123
2225
2326
2427
2528
2629
2730
2831
2932
3033
3134
3235
3337
3438
3539
3640
3741
3842
3943
4044
4145
4246
4347
4448
4549
4651
4752
4853
4954
5055
5156
5257
5358
5459
5560
5661
5762
5863
5964
6065
6166
6267
6368
6469
6570
6671
6773
6874
6975

[1,2,3,5,6,7,8,9,10,11,13,14,15,16,17,18,19,20,21,
 22,23,25,26,27,28,29,30,31,32,33,34,35,37,38,39,
 40,41,42,43,44,45,46,47,48,49,51,52,53,54,55,56,
 57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,73,
 74,75]