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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 24 |
| 4 | 71 |
| 5 | 207 |
| 6 | 603 |
| 7 | 1755 |
| 8 | 5109 |
| 9 | 14871 |
| 10 | 43290 |
| 11 | 126034 |
| 12 | 366964 |
| 13 | 1068555 |
| 14 | 3111755 |
| 15 | 9062483 |
| 16 | 26394933 |
| 17 | 76881876 |
| 18 | 223952645 |
| 19 | 652403269 |
| 20 | 1900652886 |
| 21 | 5537521144 |
| 22 | 16134412398 |
| 23 | 47012725228 |
| 24 | 136994031518 |
| 25 | 399219097098 |
[1,3,8,24,71,207,603,1755,5109,14871,43290,126034, 366964,1068555,3111755,9062483,26394933,76881876, 223952645,652403269,1900652886,5537521144, 16134412398,47012725228,136994031518,399219097098] |