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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 15 |
| 5 | 35 |
| 6 | 70 |
| 7 | 105 |
| 8 | 210 |
| 9 | 357 |
| 10 | 420 |
| 11 | 1045 |
| 12 | 1485 |
| 13 | 2090 |
| 14 | 2970 |
| 15 | 3135 |
| 16 | 3339 |
| 17 | 5049 |
| 18 | 5940 |
| 19 | 6270 |
| 20 | 10659 |
| 21 | 12441 |
| 22 | 12540 |
| 23 | 16065 |
| 24 | 24871 |
| 25 | 24969 |
| 26 | 29029 |
| 27 | 33915 |
| 28 | 35343 |
| 29 | 39105 |
| 30 | 39585 |
| 31 | 49742 |
| 32 | 50065 |
| 33 | 58058 |
| 34 | 58435 |
| 35 | 64285 |
| 36 | 70686 |
| 37 | 71145 |
| 38 | 74613 |
| 39 | 78210 |
| 40 | 87087 |
[1,3,6,15,35,70,105,210,357,420,1045,1485,2090, 2970,3135,3339,5049,5940,6270,10659,12441,12540, 16065,24871,24969,29029,33915,35343,39105,39585, 49742,50065,58058,58435,64285,70686,71145,74613, 78210,87087] |