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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 81 |
| 3 | 120 |
| 4 | 259 |
| 5 | 698 |
| 6 | 1650 |
| 7 | 3655 |
| 8 | 8544 |
| 9 | 20246 |
| 10 | 47274 |
| 11 | 110507 |
| 12 | 259419 |
| 13 | 607197 |
| 14 | 1420291 |
| 15 | 3328378 |
| 16 | 7799749 |
| 17 | 18264688 |
| 18 | 42776207 |
| 19 | 100206573 |
| 20 | 234721284 |
| 21 | 549779626 |
| 22 | 1287794595 |
| 23 | 3016512620 |
| 24 | 7065696896 |
| 25 | 16550376724 |
| 26 | 38767164617 |
| 27 | 90806809133 |
[8,81,120,259,698,1650,3655,8544,20246,47274, 110507,259419,607197,1420291,3328378,7799749, 18264688,42776207,100206573,234721284,549779626, 1287794595,3016512620,7065696896,16550376724, 38767164617,90806809133] |