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| n | a(n) |
|---|---|
| 1 | 120 |
| 2 | 628 |
| 3 | 2994 |
| 4 | 12417 |
| 5 | 47501 |
| 6 | 166904 |
| 7 | 552444 |
| 8 | 1724793 |
| 9 | 5144350 |
| 10 | 14696712 |
| 11 | 40503441 |
| 12 | 107993795 |
| 13 | 279771656 |
| 14 | 706134649 |
| 15 | 1741178487 |
| 16 | 4204576953 |
| 17 | 9961571579 |
| 18 | 23204492256 |
| 19 | 53213406141 |
| 20 | 120352868718 |
| 21 | 268716844980 |
| 22 | 593201019964 |
[120,628,2994,12417,47501,166904,552444,1724793, 5144350,14696712,40503441,107993795,279771656, 706134649,1741178487,4204576953,9961571579, 23204492256,53213406141,120352868718,268716844980, 593201019964] |