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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 6 |
| 5 | 30 |
| 6 | 5 |
| 7 | 35 |
| 8 | 280 |
| 9 | 2520 |
| 10 | 252 |
| 11 | 2772 |
| 12 | 231 |
| 13 | 3003 |
| 14 | 3003 |
| 15 | 3003 |
| 16 | 48048 |
| 17 | 816816 |
| 18 | 816816 |
| 19 | 15519504 |
| 20 | 15519504 |
| 21 | 739024 |
| 22 | 33592 |
| 23 | 772616 |
| 24 | 772616 |
| 25 | 19315400 |
| 26 | 742900 |
| 27 | 20058300 |
| 28 | 20058300 |
| 29 | 581690700 |
| 30 | 19389690 |
| 31 | 601080390 |
| 32 | 601080390 |
[1,2,6,6,30,5,35,280,2520,252,2772,231,3003,3003, 3003,48048,816816,816816,15519504,15519504,739024, 33592,772616,772616,19315400,742900,20058300, 20058300,581690700,19389690,601080390,601080390] |