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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 3 |
| 6 | 1 |
| 7 | 5 |
| 8 | 15 |
| 9 | 35 |
| 10 | 7 |
| 11 | 21 |
| 12 | 35 |
| 13 | 385 |
| 14 | 165 |
| 15 | 143 |
| 16 | 1001 |
| 17 | 15015 |
| 18 | 5005 |
| 19 | 85085 |
| 20 | 51051 |
| 21 | 46189 |
| 22 | 20995 |
| 23 | 440895 |
| 24 | 1616615 |
| 25 | 7436429 |
| 26 | 1716099 |
| 27 | 2860165 |
| 28 | 5311735 |
| 29 | 15935205 |
| 30 | 7436429 |
| 31 | 215656441 |
| 32 | 3234846615 |
[1,1,1,1,1,3,1,5,15,35,7,21,35,385,165,143,1001, 15015,5005,85085,51051,46189,20995,440895,1616615, 7436429,1716099,2860165,5311735,15935205,7436429, 215656441,3234846615] |