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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 56 |
| 4 | 234 |
| 5 | 815 |
| 6 | 2504 |
| 7 | 7018 |
| 8 | 18336 |
| 9 | 45328 |
| 10 | 107160 |
| 11 | 244198 |
| 12 | 539656 |
| 13 | 1161987 |
| 14 | 2446906 |
| 15 | 5054440 |
| 16 | 10266850 |
| 17 | 20549117 |
| 18 | 40595568 |
| 19 | 79271188 |
| 20 | 153190480 |
| 21 | 293278496 |
| 22 | 556737696 |
| 23 | 1048772300 |
| 24 | 1961855408 |
| 25 | 3646420325 |
| 26 | 6737649754 |
[1,10,56,234,815,2504,7018,18336,45328,107160, 244198,539656,1161987,2446906,5054440,10266850, 20549117,40595568,79271188,153190480,293278496, 556737696,1048772300,1961855408,3646420325, 6737649754] |