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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 5 |
| 4 | 105 |
| 5 | 63 |
| 6 | 1155 |
| 7 | 6435 |
| 8 | 45045 |
| 9 | 85085 |
| 10 | 2909907 |
| 11 | 1322685 |
| 12 | 111546435 |
| 13 | 128707425 |
| 14 | 717084225 |
| 15 | 9704539845 |
| 16 | 4512611027925 |
| 17 | 265447707525 |
| 18 | 501401225325 |
| 19 | 8787716212275 |
| 20 | 33393321606645 |
[1,3,5,105,63,1155,6435,45045,85085,2909907, 1322685,111546435,128707425,717084225,9704539845, 4512611027925,265447707525,501401225325, 8787716212275,33393321606645] |