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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 6 |
| 3 | 9 |
| 4 | 15 |
| 5 | 30 |
| 6 | 105 |
| 7 | 420 |
| 8 | 1155 |
| 9 | 2310 |
| 10 | 15015 |
| 11 | 30030 |
| 12 | 255255 |
| 13 | 1021020 |
| 14 | 4849845 |
| 15 | 19399380 |
| 16 | 111546435 |
| 17 | 669278610 |
| 18 | 9704539845 |
| 19 | 38818159380 |
| 20 | 100280245065 |
| 21 | 601681470390 |
| 22 | 14841476269620 |
| 23 | 18551845337025 |
| 24 | 152125131763605 |
[4,6,9,15,30,105,420,1155,2310,15015,30030,255255, 1021020,4849845,19399380,111546435,669278610, 9704539845,38818159380,100280245065,601681470390, 14841476269620,18551845337025,152125131763605] |