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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 11 |
| 3 | 4 |
| 4 | 31 |
| 5 | 219 |
| 6 | 579 |
| 7 | 1858 |
| 8 | 8891 |
| 9 | 34212 |
| 10 | 128103 |
| 11 | 538967 |
| 12 | 2219296 |
| 13 | 8764075 |
| 14 | 36216096 |
| 15 | 148454907 |
| 16 | 602014960 |
| 17 | 2469409541 |
| 18 | 10115533795 |
| 19 | 41307139499 |
| 20 | 169152390705 |
| 21 | 692711105743 |
| 22 | 2833870255179 |
| 23 | 11601723412009 |
| 24 | 47502652641814 |
[0,11,4,31,219,579,1858,8891,34212,128103,538967, 2219296,8764075,36216096,148454907,602014960, 2469409541,10115533795,41307139499,169152390705, 692711105743,2833870255179,11601723412009, 47502652641814] |