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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 10 |
| 5 | 58 |
| 6 | 236 |
| 7 | 836 |
| 8 | 2766 |
| 9 | 8814 |
| 10 | 27472 |
| 11 | 84472 |
| 12 | 257522 |
| 13 | 780770 |
| 14 | 2358708 |
| 15 | 7108908 |
| 16 | 21392278 |
| 17 | 64307926 |
| 18 | 193185944 |
| 19 | 580082144 |
| 20 | 1741295034 |
| 21 | 5225982282 |
| 22 | 15682141180 |
| 23 | 47054812180 |
| 24 | 141181213790 |
| 25 | 423577195838 |
| 26 | 1270798696416 |
[0,10,58,236,836,2766,8814,27472,84472,257522, 780770,2358708,7108908,21392278,64307926, 193185944,580082144,1741295034,5225982282, 15682141180,47054812180,141181213790,423577195838, 1270798696416] |