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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 15 |
| 4 | 35 |
| 5 | 77 |
| 6 | 165 |
| 7 | 330 |
| 8 | 165 |
| 9 | 105 |
| 10 | 168 |
| 11 | 616 |
| 12 | 7777 |
| 13 | 13635 |
| 14 | 23760 |
| 15 | 3696 |
| 16 | 2079 |
| 17 | 10395 |
| 18 | 5390 |
| 19 | 307230 |
| 20 | 15048 |
| 21 | 132264 |
| 22 | 1257510 |
| 23 | 395325 |
| 24 | 3083850 |
| 25 | 2384844 |
| 26 | 523740 |
| 27 | 2797795 |
| 28 | 140270 |
| 29 | 25582260 |
| 30 | 19171284 |
| 31 | 5193078 |
| 32 | 1227303 |
| 33 | 124860330 |
| 34 | 183209730 |
| 35 | 267551691 |
| 36 | 388968349 |
| 37 | 51171505 |
| 38 | 14750505 |
[1,2,6,15,35,77,165,330,165,105,168,616,7777, 13635,23760,3696,2079,10395,5390,307230,15048, 132264,1257510,395325,3083850,2384844,523740, 2797795,140270,25582260,19171284,5193078,1227303, 124860330,183209730,267551691,388968349,51171505, 14750505] |