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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 37 |
| 3 | 842 |
| 4 | 18252 |
| 5 | 405408 |
| 6 | 9268549 |
| 7 | 216864652 |
| 8 | 5165454442 |
| 9 | 124762262630 |
| 10 | 3047235458767 |
| 11 | 75109521108771 |
| 12 | 1865470016184352 |
| 13 | 46631215889276662 |
| 14 | 1172088706950306293 |
| 15 | 29601905040172054928 |
| 16 | 750748513858793527974 |
| 17 | 19110455782881086439234 |
| 18 | 488057675380082251617235 |
[0,1,37,842,18252,405408,9268549,216864652, 5165454442,124762262630,3047235458767, 75109521108771,1865470016184352,46631215889276662, 1172088706950306293,29601905040172054928, 750748513858793527974,19110455782881086439234, 488057675380082251617235] |