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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 133 |
| 4 | 366 |
| 5 | 16105 |
| 6 | 44289 |
| 7 | 1948717 |
| 8 | 5358972 |
| 9 | 235794769 |
| 10 | 648435615 |
| 11 | 28531167061 |
| 12 | 78460709418 |
| 13 | 3452271214393 |
| 14 | 9493745839581 |
| 15 | 417724816941565 |
| 16 | 1148743246589304 |
| 17 | 50544702849929377 |
| 18 | 138997932837305787 |
[0,1,3,133,366,16105,44289,1948717,5358972, 235794769,648435615,28531167061,78460709418, 3452271214393,9493745839581,417724816941565, 1148743246589304,50544702849929377, 138997932837305787] |