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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 27 |
| 3 | 99 |
| 4 | 413 |
| 5 | 1601 |
| 6 | 6349 |
| 7 | 25153 |
| 8 | 99287 |
| 9 | 392907 |
| 10 | 1553391 |
| 11 | 6142251 |
| 12 | 24289277 |
| 13 | 96042921 |
| 14 | 379779797 |
| 15 | 1501741049 |
| 16 | 5938235583 |
| 17 | 23481235283 |
| 18 | 92850420759 |
| 19 | 367152906387 |
| 20 | 1451810964181 |
| 21 | 5740809545409 |
| 22 | 22700542022605 |
| 23 | 89763402870129 |
[7,27,99,413,1601,6349,25153,99287,392907,1553391, 6142251,24289277,96042921,379779797,1501741049, 5938235583,23481235283,92850420759,367152906387, 1451810964181,5740809545409,22700542022605, 89763402870129] |