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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 105 |
| 4 | 210 |
| 5 | 20349 |
| 6 | 36075 |
| 7 | 40698 |
| 8 | 72150 |
| 9 | 7162155 |
| 10 | 9258795 |
| 11 | 14324310 |
| 12 | 18517590 |
| 13 | 117972855 |
| 14 | 156818025 |
| 15 | 235945710 |
| 16 | 313636050 |
| 17 | 5448196215 |
| 18 | 10896392430 |
[1,2,105,210,20349,36075,40698,72150,7162155, 9258795,14324310,18517590,117972855,156818025, 235945710,313636050,5448196215,10896392430] |