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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 28 |
| 4 | 111 |
| 5 | 441 |
| 6 | 1758 |
| 7 | 7110 |
| 8 | 29101 |
| 9 | 120003 |
| 10 | 497598 |
| 11 | 2073074 |
| 12 | 8671473 |
| 13 | 36394155 |
| 14 | 153183348 |
| 15 | 646345300 |
| 16 | 2733100395 |
| 17 | 11579042025 |
| 18 | 49138564920 |
| 19 | 208846332468 |
| 20 | 888831570633 |
| 21 | 3787421110239 |
| 22 | 16156612556814 |
| 23 | 68991749120934 |
| 24 | 294881166562561 |
| 25 | 1261442199126447 |
[1,3,8,28,111,441,1758,7110,29101,120003,497598, 2073074,8671473,36394155,153183348,646345300, 2733100395,11579042025,49138564920,208846332468, 888831570633,3787421110239,16156612556814, 68991749120934,294881166562561,1261442199126447] |