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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 34 |
| 3 | 223 |
| 4 | 1469 |
| 5 | 9672 |
| 6 | 63685 |
| 7 | 419329 |
| 8 | 2761042 |
| 9 | 18179883 |
| 10 | 119704137 |
| 11 | 788183312 |
| 12 | 5189736537 |
| 13 | 34171448333 |
| 14 | 224999452834 |
| 15 | 1481492773799 |
| 16 | 9754783005797 |
| 17 | 64229669677144 |
| 18 | 422915657312253 |
| 19 | 2784657839576297 |
| 20 | 18335379997029650 |
[1,5,34,223,1469,9672,63685,419329,2761042, 18179883,119704137,788183312,5189736537, 34171448333,224999452834,1481492773799, 9754783005797,64229669677144,422915657312253, 2784657839576297,18335379997029650] |