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| n | a(n) |
|---|---|
| 1 | 24 |
| 2 | 60 |
| 3 | 142 |
| 4 | 329 |
| 5 | 758 |
| 6 | 1743 |
| 7 | 4009 |
| 8 | 9223 |
| 9 | 21227 |
| 10 | 48864 |
| 11 | 112503 |
| 12 | 259042 |
| 13 | 596486 |
| 14 | 1373534 |
| 15 | 3162900 |
| 16 | 7283395 |
| 17 | 16771972 |
| 18 | 38622017 |
| 19 | 88937775 |
| 20 | 204803649 |
| 21 | 471616777 |
| 22 | 1086027506 |
| 23 | 2500877597 |
| 24 | 5758959852 |
| 25 | 13261592356 |
| 26 | 30538471600 |
| 27 | 70323248330 |
[24,60,142,329,758,1743,4009,9223,21227,48864, 112503,259042,596486,1373534,3162900,7283395, 16771972,38622017,88937775,204803649,471616777, 1086027506,2500877597,5758959852,13261592356, 30538471600,70323248330] |