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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 36 |
| 5 | 103 |
| 6 | 301 |
| 7 | 890 |
| 8 | 2649 |
| 9 | 7913 |
| 10 | 23684 |
| 11 | 70963 |
| 12 | 212745 |
| 13 | 638002 |
| 14 | 1913629 |
| 15 | 5740277 |
| 16 | 17219844 |
| 17 | 51657935 |
| 18 | 154971221 |
| 19 | 464909482 |
| 20 | 1394721681 |
| 21 | 4184154097 |
| 22 | 12552444580 |
| 23 | 37657305083 |
| 24 | 112971868881 |
| 25 | 338915531618 |
| 26 | 1016746473461 |
[1,2,5,13,36,103,301,890,2649,7913,23684,70963, 212745,638002,1913629,5740277,17219844,51657935, 154971221,464909482,1394721681,4184154097, 12552444580,37657305083,112971868881,338915531618, 1016746473461] |