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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 17 |
| 3 | 100 |
| 4 | 475 |
| 5 | 2843 |
| 6 | 16691 |
| 7 | 105026 |
| 8 | 668777 |
| 9 | 4379697 |
| 10 | 29069769 |
| 11 | 195897417 |
| 12 | 1334255973 |
| 13 | 9178287643 |
| 14 | 63648492949 |
| 15 | 444568586864 |
| 16 | 3124500279731 |
| 17 | 22080853944311 |
| 18 | 156808387564259 |
| 19 | 1118463885704019 |
| 20 | 8009066218515015 |
[1,8,17,100,475,2843,16691,105026,668777,4379697, 29069769,195897417,1334255973,9178287643, 63648492949,444568586864,3124500279731, 22080853944311,156808387564259,1118463885704019, 8009066218515015] |