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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 22 |
| 4 | 73 |
| 5 | 240 |
| 6 | 818 |
| 7 | 2824 |
| 8 | 10004 |
| 9 | 36252 |
| 10 | 134594 |
| 11 | 512632 |
| 12 | 2002797 |
| 13 | 8037634 |
| 14 | 33122211 |
| 15 | 140287074 |
| 16 | 610344666 |
| 17 | 2728599114 |
| 18 | 12524559427 |
| 19 | 59014996342 |
| 20 | 285169596358 |
| 21 | 1412357461074 |
| 22 | 7161541766341 |
| 23 | 37150562120334 |
| 24 | 196945057245451 |
| 25 | 1066104659977212 |
[1,2,7,22,73,240,818,2824,10004,36252,134594, 512632,2002797,8037634,33122211,140287074, 610344666,2728599114,12524559427,59014996342, 285169596358,1412357461074,7161541766341, 37150562120334,196945057245451,1066104659977212] |