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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 33 |
| 4 | 106 |
| 5 | 336 |
| 6 | 1056 |
| 7 | 3296 |
| 8 | 10234 |
| 9 | 31648 |
| 10 | 97551 |
| 11 | 299888 |
| 12 | 919865 |
| 13 | 2816291 |
| 14 | 8608712 |
| 15 | 26278538 |
| 16 | 80120533 |
| 17 | 244022331 |
| 18 | 742525242 |
| 19 | 2257527861 |
| 20 | 6858558246 |
| 21 | 20822959508 |
| 22 | 63181453350 |
| 23 | 191601205342 |
| 24 | 580749971840 |
| 25 | 1759465640586 |
[1,3,10,33,106,336,1056,3296,10234,31648,97551, 299888,919865,2816291,8608712,26278538,80120533, 244022331,742525242,2257527861,6858558246, 20822959508,63181453350,191601205342,580749971840, 1759465640586] |