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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 27 |
| 2 | 111 |
| 3 | 378 |
| 4 | 1356 |
| 5 | 4131 |
| 6 | 10881 |
| 7 | 29106 |
| 8 | 73500 |
| 9 | 167643 |
| 10 | 382053 |
| 11 | 849339 |
| 12 | 1754061 |
| 13 | 3605094 |
| 14 | 7330311 |
| 15 | 14094945 |
| 16 | 26980563 |
| 17 | 51481332 |
| 18 | 93965784 |
| 19 | 170910270 |
| 20 | 311155296 |
| 21 | 545970024 |
| 22 | 955201653 |
| 23 | 1676274750 |
| 24 | 2849709768 |
| 25 | 4831999623 |
[3,27,111,378,1356,4131,10881,29106,73500,167643, 382053,849339,1754061,3605094,7330311,14094945, 26980563,51481332,93965784,170910270,311155296, 545970024,955201653,1676274750,2849709768, 4831999623] |