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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 48 |
| 3 | 128 |
| 4 | 302 |
| 5 | 704 |
| 6 | 1622 |
| 7 | 3696 |
| 8 | 8626 |
| 9 | 19784 |
| 10 | 47062 |
| 11 | 109280 |
| 12 | 264218 |
| 13 | 620192 |
| 14 | 1517126 |
| 15 | 3588888 |
| 16 | 8847682 |
| 17 | 21038192 |
| 18 | 52125406 |
| 19 | 124356752 |
| 20 | 309096434 |
| 21 | 738979400 |
| 22 | 1840516550 |
| 23 | 4406202720 |
| 24 | 10988503498 |
| 25 | 26329344800 |
| 26 | 65717431510 |
| 27 | 157552717784 |
[16,48,128,302,704,1622,3696,8626,19784,47062, 109280,264218,620192,1517126,3588888,8847682, 21038192,52125406,124356752,309096434,738979400, 1840516550,4406202720,10988503498,26329344800, 65717431510,157552717784] |