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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 19 |
| 4 | 209 |
| 5 | 3545 |
| 6 | 85803 |
| 7 | 2807723 |
| 8 | 119377321 |
| 9 | 6397099105 |
| 10 | 421772316915 |
| 11 | 33552418294339 |
| 12 | 3168847554832961 |
| 13 | 350514662908385321 |
| 14 | 44885099167514403963 |
| 15 | 6587836555407268741019 |
| 16 | 1098597117953239632728089 |
| 17 | 206564512095561068049417265 |
| 18 | 43495029251774783469442768323 |
[1,1,3,19,209,3545,85803,2807723,119377321, 6397099105,421772316915,33552418294339, 3168847554832961,350514662908385321, 44885099167514403963,6587836555407268741019, 1098597117953239632728089, 206564512095561068049417265, 43495029251774783469442768323] |