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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 34 |
| 4 | 255 |
| 5 | 2005 |
| 6 | 15999 |
| 7 | 128319 |
| 8 | 1030709 |
| 9 | 8283143 |
| 10 | 66576711 |
| 11 | 535145269 |
| 12 | 4301582207 |
| 13 | 34576983087 |
| 14 | 277937230517 |
| 15 | 2234120533079 |
| 16 | 17958355078007 |
| 17 | 144353239501301 |
| 18 | 1160343364887311 |
| 19 | 9327097456058015 |
| 20 | 74973279259758837 |
[1,6,34,255,2005,15999,128319,1030709,8283143, 66576711,535145269,4301582207,34576983087, 277937230517,2234120533079,17958355078007, 144353239501301,1160343364887311,9327097456058015, 74973279259758837] |