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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 111 |
| 3 | 1260 |
| 4 | 1707 |
| 5 | 2280 |
| 6 | 8791 |
| 7 | 11380 |
| 8 | 14707 |
| 9 | 52624 |
| 10 | 67711 |
| 11 | 87100 |
| 12 | 308091 |
| 13 | 396024 |
| 14 | 509031 |
| 15 | 1797060 |
| 16 | 2309571 |
| 17 | 2968224 |
| 18 | 10475407 |
| 19 | 13462540 |
| 20 | 17301451 |
| 21 | 61056520 |
| 22 | 78466807 |
| 23 | 100841620 |
| 24 | 355864851 |
| 25 | 457339440 |
| 26 | 587749407 |
| 27 | 2074133724 |
| 28 | 2665570971 |
[0,111,1260,1707,2280,8791,11380,14707,52624, 67711,87100,308091,396024,509031,1797060,2309571, 2968224,10475407,13462540,17301451,61056520, 78466807,100841620,355864851,457339440,587749407, 2074133724,2665570971] |