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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 24 |
| 3 | 51 |
| 4 | 132 |
| 5 | 502 |
| 6 | 1638 |
| 7 | 4816 |
| 8 | 15697 |
| 9 | 51711 |
| 10 | 162366 |
| 11 | 515716 |
| 12 | 1666971 |
| 13 | 5329280 |
| 14 | 16966976 |
| 15 | 54361108 |
| 16 | 174123735 |
| 17 | 556206198 |
| 18 | 1778536970 |
| 19 | 5692126701 |
| 20 | 18203527304 |
| 21 | 58206977546 |
| 22 | 186193045751 |
| 23 | 595556243811 |
| 24 | 1904654103039 |
| 25 | 6091785970264 |
[8,24,51,132,502,1638,4816,15697,51711,162366, 515716,1666971,5329280,16966976,54361108, 174123735,556206198,1778536970,5692126701, 18203527304,58206977546,186193045751,595556243811, 1904654103039,6091785970264] |