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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 13 |
| 4 | 23 |
| 5 | 45 |
| 6 | 131 |
| 7 | 337 |
| 8 | 883 |
| 9 | 2389 |
| 10 | 6599 |
| 11 | 18393 |
| 12 | 51475 |
| 13 | 144777 |
| 14 | 408787 |
| 15 | 1156245 |
| 16 | 3275327 |
| 17 | 9287881 |
| 18 | 26355499 |
| 19 | 74822993 |
| 20 | 212488499 |
| 21 | 603573125 |
| 22 | 1714703255 |
| 23 | 4871817065 |
| 24 | 13842752035 |
| 25 | 39334524393 |
| 26 | 111773515363 |
| 27 | 317623880677 |
[1,7,13,23,45,131,337,883,2389,6599,18393,51475, 144777,408787,1156245,3275327,9287881,26355499, 74822993,212488499,603573125,1714703255, 4871817065,13842752035,39334524393,111773515363, 317623880677] |