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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 15 |
| 4 | 46 |
| 5 | 161 |
| 6 | 624 |
| 7 | 2669 |
| 8 | 12483 |
| 9 | 63261 |
| 10 | 344631 |
| 11 | 2005058 |
| 12 | 12390086 |
| 13 | 80945545 |
| 14 | 556896913 |
| 15 | 4021109557 |
| 16 | 30382294412 |
| 17 | 239589006143 |
| 18 | 1967343509525 |
| 19 | 16786587081641 |
| 20 | 148561276135546 |
| 21 | 1361378815644787 |
| 22 | 12897870827339021 |
| 23 | 126158299918183469 |
| 24 | 1272377007364596242 |
[1,2,5,15,46,161,624,2669,12483,63261,344631, 2005058,12390086,80945545,556896913,4021109557, 30382294412,239589006143,1967343509525, 16786587081641,148561276135546,1361378815644787, 12897870827339021,126158299918183469, 1272377007364596242] |