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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 15 |
| 5 | 21 |
| 6 | 28 |
| 7 | 36 |
| 8 | 45 |
| 9 | 55 |
| 10 | 66 |
| 11 | 78 |
| 12 | 91 |
| 13 | 136 |
| 14 | 171 |
| 15 | 231 |
| 16 | 276 |
| 17 | 378 |
| 18 | 406 |
| 19 | 435 |
| 20 | 465 |
| 21 | 528 |
| 22 | 561 |
| 23 | 595 |
| 24 | 666 |
| 25 | 703 |
| 26 | 741 |
| 27 | 861 |
| 28 | 903 |
| 29 | 990 |
| 30 | 1081 |
| 31 | 1128 |
| 32 | 1176 |
| 33 | 1225 |
| 34 | 1275 |
| 35 | 1326 |
| 36 | 1431 |
| 37 | 1540 |
| 38 | 1596 |
| 39 | 1653 |
| 40 | 1711 |
| 41 | 1770 |
| 42 | 1953 |
| 43 | 2016 |
| 44 | 2211 |
| 45 | 2278 |
| 46 | 2346 |
| 47 | 2485 |
| 48 | 2556 |
| 49 | 2628 |
| 50 | 2775 |
[1,3,6,15,21,28,36,45,55,66,78,91,136,171,231,276, 378,406,435,465,528,561,595,666,703,741,861,903, 990,1081,1128,1176,1225,1275,1326,1431,1540,1596, 1653,1711,1770,1953,2016,2211,2278,2346,2485,2556, 2628,2775] |