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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 36 |
| 4 | 204 |
| 5 | 1002 |
| 6 | 5244 |
| 7 | 26328 |
| 8 | 133476 |
| 9 | 667335 |
| 10 | 3331117 |
| 11 | 16516607 |
| 12 | 81607176 |
| 13 | 401407499 |
| 14 | 1967534543 |
| 15 | 9609826869 |
| 16 | 46788348316 |
| 17 | 227114265649 |
| 18 | 1099339308308 |
| 19 | 5307155062783 |
| 20 | 25556511343601 |
| 21 | 122773840789344 |
| 22 | 588473630650319 |
| 23 | 2814565652799711 |
| 24 | 13433897987956859 |
[1,1,8,36,204,1002,5244,26328,133476,667335, 3331117,16516607,81607176,401407499,1967534543, 9609826869,46788348316,227114265649,1099339308308, 5307155062783,25556511343601,122773840789344, 588473630650319,2814565652799711, 13433897987956859] |