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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 2 |
| 7 | 9 |
| 8 | 26 |
| 9 | 87 |
| 10 | 257 |
| 11 | 787 |
| 12 | 2322 |
| 13 | 6891 |
| 14 | 20160 |
| 15 | 58939 |
| 16 | 171203 |
| 17 | 496294 |
| 18 | 1433558 |
| 19 | 4132744 |
| 20 | 11886827 |
| 21 | 34133563 |
| 22 | 97856500 |
| 23 | 280172582 |
| 24 | 801174478 |
| 25 | 2288600128 |
| 26 | 6531205571 |
| 27 | 18622839635 |
| 28 | 53059229091 |
| 29 | 151067980960 |
| 30 | 429840337630 |
| 31 | 1222335365450 |
| 32 | 3474107883033 |
| 33 | 9869276762717 |
[1,2,9,26,87,257,787,2322,6891,20160,58939,171203, 496294,1433558,4132744,11886827,34133563,97856500, 280172582,801174478,2288600128,6531205571, 18622839635,53059229091,151067980960,429840337630, 1222335365450,3474107883033,9869276762717] |