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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 5 |
| 6 | 15 |
| 7 | 315 |
| 8 | 630 |
| 9 | 567 |
| 10 | 1134 |
| 11 | 4725 |
| 12 | 9450 |
| 13 | 26325 |
| 14 | 28665 |
| 15 | 116093250 |
| 16 | 116093250 |
| 17 | 7894341000 |
| 18 | 8881133625 |
| 19 | 14849255421000 |
| 20 | 4242644406000 |
| 21 | 3118343638410000 |
| 22 | 3811308891390000 |
| 23 | 34301780022510000 |
| 24 | 205810680135060000 |
| 25 | 1470076286679000000 |
| 26 | 2702564486622000000 |
[1,1,1,3,3,5,15,315,630,567,1134,4725,9450,26325, 28665,116093250,116093250,7894341000,8881133625, 14849255421000,4242644406000,3118343638410000, 3811308891390000,34301780022510000, 205810680135060000,1470076286679000000, 2702564486622000000] |