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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 35 |
| 5 | 6 |
| 6 | 924 |
| 7 | 8 |
| 8 | 6435 |
| 9 | 715 |
| 10 | 43758 |
| 11 | 12 |
| 12 | 30421755 |
| 13 | 14 |
| 14 | 1961256 |
| 15 | 1307504 |
| 16 | 300540195 |
| 17 | 18 |
| 18 | 62359143990 |
| 19 | 20 |
| 20 | 513791607420 |
| 21 | 129024480 |
| 22 | 3796297200 |
| 23 | 24 |
| 24 | 36052387482172425 |
| 25 | 736281 |
| 26 | 166509721602 |
| 27 | 12033222880 |
| 28 | 7648690600760440 |
| 29 | 30 |
[1,3,4,35,6,924,8,6435,715,43758,12,30421755,14, 1961256,1307504,300540195,18,62359143990,20, 513791607420,129024480,3796297200,24, 36052387482172425,736281,166509721602,12033222880, 7648690600760440,30] |