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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 46 |
| 6 | 165 |
| 7 | 651 |
| 8 | 2771 |
| 9 | 12638 |
| 10 | 61398 |
| 11 | 315562 |
| 12 | 1709960 |
| 13 | 9723253 |
| 14 | 57831688 |
| 15 | 358445901 |
| 16 | 2306799588 |
| 17 | 15354546420 |
| 18 | 105275618325 |
| 19 | 740481162174 |
| 20 | 5321875886529 |
| 21 | 38940082552276 |
| 22 | 289132258826130 |
| 23 | 2172495189822333 |
| 24 | 16480880960094288 |
| 25 | 125993420982428718 |
[1,1,2,5,14,46,165,651,2771,12638,61398,315562, 1709960,9723253,57831688,358445901,2306799588, 15354546420,105275618325,740481162174, 5321875886529,38940082552276,289132258826130, 2172495189822333,16480880960094288, 125993420982428718] |