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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 10 |
| 5 | 15 |
| 6 | 21 |
| 7 | 28 |
| 8 | 66 |
| 9 | 105 |
| 10 | 120 |
| 11 | 153 |
| 12 | 171 |
| 13 | 435 |
| 14 | 561 |
| 15 | 946 |
| 16 | 1378 |
| 17 | 1485 |
| 18 | 3916 |
| 19 | 4005 |
| 20 | 4278 |
| 21 | 4851 |
| 22 | 4950 |
| 23 | 11781 |
| 24 | 14365 |
| 25 | 15576 |
| 26 | 47586 |
| 27 | 50086 |
| 28 | 51360 |
| 29 | 57970 |
| 30 | 60378 |
| 31 | 60726 |
| 32 | 61425 |
| 33 | 61776 |
| 34 | 139128 |
| 35 | 145530 |
| 36 | 146070 |
| 37 | 149878 |
| 38 | 150426 |
| 39 | 182710 |
| 40 | 659526 |
| 41 | 702705 |
[1,3,6,10,15,21,28,66,105,120,153,171,435,561,946, 1378,1485,3916,4005,4278,4851,4950,11781,14365, 15576,47586,50086,51360,57970,60378,60726,61425, 61776,139128,145530,146070,149878,150426,182710, 659526,702705] |