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| n | a(n) |
|---|---|
| 1 | 14 |
| 2 | 72 |
| 3 | 396 |
| 4 | 2160 |
| 5 | 11808 |
| 6 | 64512 |
| 7 | 352512 |
| 8 | 1926144 |
| 9 | 10524672 |
| 10 | 57507840 |
| 11 | 314228736 |
| 12 | 1716977664 |
| 13 | 9381740544 |
| 14 | 51262783488 |
| 15 | 280105058304 |
| 16 | 1530522501120 |
| 17 | 8362930470912 |
| 18 | 45695901892608 |
| 19 | 249687051337728 |
| 20 | 1364315420491776 |
[14,72,396,2160,11808,64512,352512,1926144, 10524672,57507840,314228736,1716977664,9381740544, 51262783488,280105058304,1530522501120, 8362930470912,45695901892608,249687051337728, 1364315420491776] |