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| n | a(n) |
|---|---|
| 1 | 80 |
| 2 | 216 |
| 3 | 498 |
| 4 | 1064 |
| 5 | 2200 |
| 6 | 4448 |
| 7 | 8844 |
| 8 | 17552 |
| 9 | 34384 |
| 10 | 67836 |
| 11 | 132308 |
| 12 | 260904 |
| 13 | 509178 |
| 14 | 1006144 |
| 15 | 1969566 |
| 16 | 3904484 |
| 17 | 7675178 |
| 18 | 15271538 |
| 19 | 30158642 |
| 20 | 60234204 |
| 21 | 119509036 |
| 22 | 239563440 |
| 23 | 477465048 |
| 24 | 960417468 |
| 25 | 1922353398 |
| 26 | 3879214910 |
| 27 | 7795367130 |
[80,216,498,1064,2200,4448,8844,17552,34384,67836, 132308,260904,509178,1006144,1969566,3904484, 7675178,15271538,30158642,60234204,119509036, 239563440,477465048,960417468,1922353398, 3879214910,7795367130] |