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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 27 |
| 2 | 129 |
| 3 | 483 |
| 4 | 2117 |
| 5 | 9337 |
| 6 | 42249 |
| 7 | 193493 |
| 8 | 895517 |
| 9 | 4176897 |
| 10 | 19605239 |
| 11 | 92495573 |
| 12 | 438260309 |
| 13 | 2084105193 |
| 14 | 9941672807 |
| 15 | 47552376493 |
| 16 | 227988078573 |
| 17 | 1095365516417 |
| 18 | 5272454219583 |
| 19 | 25420784798597 |
| 20 | 122748340134507 |
[1,27,129,483,2117,9337,42249,193493,895517, 4176897,19605239,92495573,438260309,2084105193, 9941672807,47552376493,227988078573,1095365516417, 5272454219583,25420784798597,122748340134507] |