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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 27 |
| 4 | 76 |
| 5 | 195 |
| 6 | 519 |
| 7 | 1299 |
| 8 | 3364 |
| 9 | 8311 |
| 10 | 21191 |
| 11 | 51981 |
| 12 | 131273 |
| 13 | 320715 |
| 14 | 804845 |
| 15 | 1961823 |
| 16 | 4901782 |
| 17 | 11932489 |
| 18 | 29719325 |
| 19 | 72291325 |
| 20 | 179610365 |
| 21 | 436699813 |
| 22 | 1082870377 |
| 23 | 2632116551 |
| 24 | 6516122403 |
| 25 | 15835522783 |
| 26 | 39147779575 |
[1,3,10,27,76,195,519,1299,3364,8311,21191,51981, 131273,320715,804845,1961823,4901782,11932489, 29719325,72291325,179610365,436699813,1082870377, 2632116551,6516122403,15835522783,39147779575] |