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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 21 |
| 5 | 55 |
| 6 | 144 |
| 7 | 377 |
| 8 | 987 |
| 9 | 2584 |
| 10 | 6765 |
| 11 | 17711 |
| 12 | 46368 |
| 13 | 121393 |
| 14 | 317811 |
| 15 | 832040 |
| 16 | 2178309 |
| 17 | 5702887 |
| 18 | 14930352 |
| 19 | 39088169 |
| 20 | 102334155 |
| 21 | 267914296 |
| 22 | 701408733 |
| 23 | 1836311903 |
| 24 | 4807526976 |
| 25 | 12586269025 |
| 26 | 32951280099 |
| 27 | 86267571272 |
| 28 | 225851433717 |
[1,1,3,8,21,55,144,377,987,2584,6765,17711,46368, 121393,317811,832040,2178309,5702887,14930352, 39088169,102334155,267914296,701408733,1836311903, 4807526976,12586269025,32951280099,86267571272, 225851433717] |