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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 12 |
| 3 | 43 |
| 4 | 145 |
| 5 | 524 |
| 6 | 1888 |
| 7 | 6737 |
| 8 | 24093 |
| 9 | 86250 |
| 10 | 308600 |
| 11 | 1104107 |
| 12 | 3950629 |
| 13 | 14135676 |
| 14 | 50578004 |
| 15 | 180970841 |
| 16 | 647524153 |
| 17 | 2316876914 |
| 18 | 8289912724 |
| 19 | 29661766587 |
| 20 | 106131439497 |
| 21 | 379744147900 |
| 22 | 1358745529912 |
| 23 | 4861666537265 |
| 24 | 17395311311589 |
[2,12,43,145,524,1888,6737,24093,86250,308600, 1104107,3950629,14135676,50578004,180970841, 647524153,2316876914,8289912724,29661766587, 106131439497,379744147900,1358745529912, 4861666537265,17395311311589] |