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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 40 |
| 3 | 188 |
| 4 | 808 |
| 5 | 3348 |
| 6 | 13884 |
| 7 | 56092 |
| 8 | 225404 |
| 9 | 904436 |
| 10 | 3640068 |
| 11 | 14600860 |
| 12 | 58510396 |
| 13 | 234316180 |
| 14 | 937995428 |
| 15 | 3753709232 |
[1,8,40,188,808,3348,13884,56092,225404,904436, 3640068,14600860,58510396,234316180,937995428, 3753709232] |