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| n | a(n) |
|---|---|
| 1 | 253 |
| 2 | 787 |
| 3 | 2237 |
| 4 | 6615 |
| 5 | 19723 |
| 6 | 57699 |
| 7 | 169561 |
| 8 | 500813 |
| 9 | 1473813 |
| 10 | 4336509 |
| 11 | 12776787 |
| 12 | 37624405 |
| 13 | 110768047 |
| 14 | 326202095 |
| 15 | 960592477 |
| 16 | 2828495527 |
| 17 | 8329036847 |
| 18 | 24526561909 |
| 19 | 72221962493 |
| 20 | 212669436487 |
| 21 | 626242809531 |
| 22 | 1844074518231 |
[253,787,2237,6615,19723,57699,169561,500813, 1473813,4336509,12776787,37624405,110768047, 326202095,960592477,2828495527,8329036847, 24526561909,72221962493,212669436487,626242809531, 1844074518231] |