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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 8 |
| 4 | 41 |
| 5 | 208 |
| 6 | 856 |
| 7 | 4540 |
| 8 | 18527 |
| 9 | 86896 |
| 10 | 343976 |
| 11 | 1794146 |
| 12 | 7114521 |
| 13 | 33019048 |
| 14 | 129946039 |
| 15 | 674164700 |
| 16 | 2656947487 |
| 17 | 12352433072 |
| 18 | 48571744683 |
| 19 | 251186392774 |
| 20 | 988685996629 |
| 21 | 4614598284024 |
| 22 | 18151637670487 |
| 23 | 93662525206528 |
| 24 | 368685987098199 |
| 25 | 1727749480803800 |
| 26 | 6800520785920773 |
[1,8,41,208,856,4540,18527,86896,343976,1794146, 7114521,33019048,129946039,674164700,2656947487, 12352433072,48571744683,251186392774,988685996629, 4614598284024,18151637670487,93662525206528, 368685987098199,1727749480803800,6800520785920773] |