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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 16 |
| 3 | 146 |
| 4 | 955 |
| 5 | 4905 |
| 6 | 20907 |
| 7 | 76851 |
| 8 | 250530 |
| 9 | 739612 |
| 10 | 2009177 |
| 11 | 5085119 |
| 12 | 12109526 |
| 13 | 27348478 |
| 14 | 58955082 |
| 15 | 121956402 |
| 16 | 243172488 |
| 17 | 469115187 |
| 18 | 878387366 |
| 19 | 1600751976 |
| 20 | 2845918041 |
| 21 | 4946262815 |
| 22 | 8419256605 |
| 23 | 14057377245 |
| 24 | 23055913530 |
| 25 | 37192403430 |
| 26 | 59075703351 |
| 27 | 92488040301 |
[0,1,16,146,955,4905,20907,76851,250530,739612, 2009177,5085119,12109526,27348478,58955082, 121956402,243172488,469115187,878387366, 1600751976,2845918041,4946262815,8419256605, 14057377245,23055913530,37192403430,59075703351, 92488040301] |