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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 10 |
| 4 | 55 |
| 5 | 150 |
| 6 | 775 |
| 7 | 2550 |
| 8 | 12500 |
| 9 | 46250 |
| 10 | 219375 |
| 11 | 875000 |
| 12 | 4075000 |
| 13 | 17071250 |
| 14 | 78796875 |
| 15 | 341100000 |
| 16 | 1569350000 |
| 17 | 6947531250 |
| 18 | 31966000000 |
| 19 | 143761750000 |
| 20 | 662668906250 |
| 21 | 3014440000000 |
| 22 | 13932834296875 |
| 23 | 63921914062500 |
| 24 | 296358191406250 |
| 25 | 1368603488281250 |
| 26 | 6365085546875000 |
[1,1,5,10,55,150,775,2550,12500,46250,219375, 875000,4075000,17071250,78796875,341100000, 1569350000,6947531250,31966000000,143761750000, 662668906250,3014440000000,13932834296875, 63921914062500,296358191406250,1368603488281250, 6365085546875000] |