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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 15 |
| 3 | 63 |
| 4 | 3 |
| 5 | 315 |
| 6 | 120 |
| 7 | 2268 |
| 8 | 102060 |
| 9 | 241920 |
| 10 | 2953125 |
| 11 | 51438240 |
| 12 | 145212480 |
| 13 | 5290790400 |
| 14 | 76545 |
| 15 | 945 |
| 16 | 15120 |
| 17 | 1071630 |
| 18 | 26127360 |
| 19 | 106312500 |
| 20 | 1050197400 |
| 21 | 95591301120 |
| 22 | 1339231320 |
| 23 | 76204800 |
| 24 | 3135283200 |
| 25 | 3511517184000 |
[1,15,63,3,315,120,2268,102060,241920,2953125, 51438240,145212480,5290790400,76545,945,15120, 1071630,26127360,106312500,1050197400,95591301120, 1339231320,76204800,3135283200,3511517184000] |