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| n | a(n) |
|---|---|
| 0 | 6 |
| 1 | 4 |
| 2 | 16 |
| 3 | 34 |
| 4 | 96 |
| 5 | 244 |
| 6 | 646 |
| 7 | 1684 |
| 8 | 4416 |
| 9 | 11554 |
| 10 | 30256 |
| 11 | 79204 |
| 12 | 207366 |
| 13 | 542884 |
| 14 | 1421296 |
| 15 | 3720994 |
| 16 | 9741696 |
| 17 | 25504084 |
| 18 | 66770566 |
| 19 | 174807604 |
| 20 | 457652256 |
| 21 | 1198149154 |
| 22 | 3136795216 |
| 23 | 8212236484 |
| 24 | 21499914246 |
| 25 | 56287506244 |
| 26 | 147362604496 |
| 27 | 385800307234 |
| 28 | 1010038317216 |
[6,4,16,34,96,244,646,1684,4416,11554,30256,79204, 207366,542884,1421296,3720994,9741696,25504084, 66770566,174807604,457652256,1198149154, 3136795216,8212236484,21499914246,56287506244, 147362604496,385800307234,1010038317216] |