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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 4 |
| 4 | 4 |
| 5 | 18 |
| 6 | 22 |
| 7 | 64 |
| 8 | 96 |
| 9 | 188 |
| 10 | 388 |
| 11 | 648 |
| 12 | 1248 |
| 13 | 2040 |
| 14 | 3784 |
| 15 | 6544 |
| 16 | 11162 |
| 17 | 19356 |
| 18 | 32396 |
| 19 | 55768 |
| 20 | 93678 |
| 21 | 157308 |
| 22 | 263308 |
| 23 | 438512 |
| 24 | 731198 |
| 25 | 1211304 |
| 26 | 2004076 |
| 27 | 3306552 |
| 28 | 5445588 |
| 29 | 8955544 |
| 30 | 14690980 |
| 31 | 24061172 |
| 32 | 39360032 |
[0,2,4,4,18,22,64,96,188,388,648,1248,2040,3784, 6544,11162,19356,32396,55768,93678,157308,263308, 438512,731198,1211304,2004076,3306552,5445588, 8955544,14690980,24061172,39360032] |