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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 16 |
| 3 | 40 |
| 4 | 98 |
| 5 | 241 |
| 6 | 591 |
| 7 | 1393 |
| 8 | 3386 |
| 9 | 8313 |
| 10 | 20393 |
| 11 | 50189 |
| 12 | 123972 |
| 13 | 308917 |
| 14 | 776173 |
| 15 | 1953900 |
| 16 | 4942615 |
| 17 | 12556599 |
| 18 | 32045879 |
| 19 | 82012870 |
| 20 | 210587095 |
| 21 | 542262360 |
| 22 | 1400124552 |
| 23 | 3623612454 |
| 24 | 9398492120 |
| 25 | 24425121427 |
| 26 | 63595807021 |
| 27 | 165867439024 |
[5,16,40,98,241,591,1393,3386,8313,20393,50189, 123972,308917,776173,1953900,4942615,12556599, 32045879,82012870,210587095,542262360,1400124552, 3623612454,9398492120,24425121427,63595807021, 165867439024] |