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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 23 |
| 4 | 95 |
| 5 | 355 |
| 6 | 1578 |
| 7 | 6274 |
| 8 | 28892 |
| 9 | 119136 |
| 10 | 560067 |
| 11 | 2365025 |
| 12 | 11269227 |
| 13 | 48392249 |
| 14 | 232747379 |
| 15 | 1012038954 |
| 16 | 4900368125 |
| 17 | 21515650107 |
| 18 | 104706189813 |
| 19 | 463307727667 |
| 20 | 2263448270060 |
| 21 | 10079357562618 |
| 22 | 49392369093859 |
| 23 | 221123954515892 |
| 24 | 1086245148195484 |
| 25 | 4885083104051388 |
| 26 | 24045498438408407 |
| 27 | 108561416724584040 |
[1,2,7,23,95,355,1578,6274,28892,119136,560067, 2365025,11269227,48392249,232747379,1012038954, 4900368125,21515650107,104706189813,463307727667, 2263448270060,10079357562618,49392369093859, 221123954515892,1086245148195484,4885083104051388, 24045498438408407,108561416724584040] |