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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 35 |
| 6 | 63 |
| 7 | 231 |
| 8 | 143 |
| 9 | 6435 |
| 10 | 12155 |
| 11 | 46189 |
| 12 | 88179 |
| 13 | 676039 |
| 14 | 1300075 |
| 15 | 5014575 |
| 16 | 9694845 |
| 17 | 100180065 |
| 18 | 116680311 |
| 19 | 2268783825 |
| 20 | 1472719325 |
| 21 | 34461632205 |
| 22 | 67282234305 |
| 23 | 17534158031 |
| 24 | 514589420475 |
| 25 | 8061900920775 |
| 26 | 5267108601573 |
[2,1,3,5,35,63,231,143,6435,12155,46189,88179, 676039,1300075,5014575,9694845,100180065, 116680311,2268783825,1472719325,34461632205, 67282234305,17534158031,514589420475, 8061900920775,5267108601573] |