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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 49 |
| 3 | 211 |
| 4 | 847 |
| 5 | 3282 |
| 6 | 12405 |
| 7 | 45860 |
| 8 | 167525 |
| 9 | 605878 |
| 10 | 2177496 |
| 11 | 7787333 |
| 12 | 27757367 |
| 13 | 98687854 |
| 14 | 350247594 |
| 15 | 1241371867 |
| 16 | 4395505741 |
| 17 | 15552531864 |
| 18 | 55000200159 |
| 19 | 194426956404 |
| 20 | 687105218857 |
| 21 | 2427709127594 |
| 22 | 8576325199050 |
| 23 | 30293865359314 |
[7,49,211,847,3282,12405,45860,167525,605878, 2177496,7787333,27757367,98687854,350247594, 1241371867,4395505741,15552531864,55000200159, 194426956404,687105218857,2427709127594, 8576325199050,30293865359314] |