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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 3 |
| 3 | 6 |
| 4 | 15 |
| 5 | 21 |
| 6 | 36 |
| 7 | 45 |
| 8 | 66 |
| 9 | 78 |
| 10 | 105 |
| 11 | 120 |
| 12 | 153 |
| 13 | 171 |
| 14 | 210 |
| 15 | 231 |
| 16 | 276 |
| 17 | 300 |
| 18 | 351 |
| 19 | 378 |
| 20 | 435 |
| 21 | 465 |
| 22 | 528 |
| 23 | 561 |
| 24 | 630 |
| 25 | 666 |
| 26 | 741 |
| 27 | 780 |
| 28 | 861 |
| 29 | 903 |
| 30 | 990 |
| 31 | 1035 |
| 32 | 1128 |
| 33 | 1176 |
| 34 | 1275 |
| 35 | 1326 |
| 36 | 1431 |
| 37 | 1485 |
| 38 | 1596 |
| 39 | 1653 |
| 40 | 1770 |
| 41 | 1830 |
| 42 | 1953 |
| 43 | 2016 |
| 44 | 2145 |
| 45 | 2211 |
| 46 | 2346 |
| 47 | 2415 |
| 48 | 2556 |
| 49 | 2628 |
| 50 | 2775 |
[0,3,6,15,21,36,45,66,78,105,120,153,171,210,231, 276,300,351,378,435,465,528,561,630,666,741,780, 861,903,990,1035,1128,1176,1275,1326,1431,1485, 1596,1653,1770,1830,1953,2016,2145,2211,2346,2415, 2556,2628,2775] |