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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 4 |
| 2 | 8 |
| 3 | 24 |
| 4 | 40 |
| 5 | 144 |
| 6 | 256 |
| 7 | 768 |
| 8 | 1408 |
| 9 | 4736 |
| 10 | 8064 |
| 11 | 29440 |
| 12 | 51712 |
| 13 | 168960 |
| 14 | 303104 |
| 15 | 1056768 |
| 16 | 1810432 |
| 17 | 6651904 |
| 18 | 11632640 |
| 19 | 39452672 |
| 20 | 70090752 |
| 21 | 248676352 |
| 22 | 427261952 |
| 23 | 1575419904 |
| 24 | 2748710912 |
| 25 | 9519759360 |
| 26 | 16819683328 |
| 27 | 60294692864 |
[2,4,8,24,40,144,256,768,1408,4736,8064,29440, 51712,168960,303104,1056768,1810432,6651904, 11632640,39452672,70090752,248676352,427261952, 1575419904,2748710912,9519759360,16819683328, 60294692864] |