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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 25 |
| 5 | 81 |
| 6 | 274 |
| 7 | 953 |
| 8 | 3389 |
| 9 | 12265 |
| 10 | 45025 |
| 11 | 167256 |
| 12 | 627540 |
| 13 | 2374672 |
| 14 | 9052447 |
| 15 | 34731401 |
| 16 | 134010573 |
| 17 | 519683813 |
| 18 | 2024370167 |
| 19 | 7917605996 |
| 20 | 31080085431 |
| 21 | 122407860927 |
| 22 | 483558273368 |
| 23 | 1915535953655 |
| 24 | 7607408410408 |
| 25 | 30283240593756 |
[1,1,3,8,25,81,274,953,3389,12265,45025,167256, 627540,2374672,9052447,34731401,134010573, 519683813,2024370167,7917605996,31080085431, 122407860927,483558273368,1915535953655, 7607408410408,30283240593756] |