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| n | a(n) |
|---|---|
| 1 | 273 |
| 2 | 1491 |
| 3 | 8239 |
| 4 | 45465 |
| 5 | 250913 |
| 6 | 1384813 |
| 7 | 7642875 |
| 8 | 42181611 |
| 9 | 232803603 |
| 10 | 1284861277 |
| 11 | 7091249941 |
| 12 | 39137163521 |
| 13 | 216001069269 |
| 14 | 1192126810953 |
| 15 | 6579441195743 |
| 16 | 36312451033865 |
| 17 | 200411259993515 |
| 18 | 1106085433196691 |
[273,1491,8239,45465,250913,1384813,7642875, 42181611,232803603,1284861277,7091249941, 39137163521,216001069269,1192126810953, 6579441195743,36312451033865,200411259993515, 1106085433196691] |