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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 9 |
| 5 | 23 |
| 6 | 43 |
| 7 | 113 |
| 8 | 331 |
| 9 | 698 |
| 10 | 1966 |
| 11 | 4072 |
| 12 | 11433 |
| 13 | 23701 |
| 14 | 66734 |
| 15 | 205712 |
| 16 | 459632 |
| 17 | 1348864 |
| 18 | 2927822 |
| 19 | 8499580 |
| 20 | 26809375 |
| 21 | 61495590 |
| 22 | 183946295 |
| 23 | 408179706 |
| 24 | 1204202538 |
| 25 | 2643267587 |
[1,2,5,9,23,43,113,331,698,1966,4072,11433,23701, 66734,205712,459632,1348864,2927822,8499580, 26809375,61495590,183946295,408179706,1204202538, 2643267587] |