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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 5 |
| 3 | 135 |
| 4 | 1800 |
| 5 | 19919 |
| 6 | 206964 |
| 7 | 2086746 |
| 8 | 20710806 |
| 9 | 203834084 |
| 10 | 1997171674 |
| 11 | 19522428788 |
| 12 | 190614467420 |
| 13 | 1860310801454 |
| 14 | 18155356377267 |
| 15 | 177224592578839 |
| 16 | 1730651760050923 |
| 17 | 16908343191198752 |
| 18 | 165279853754232019 |
| 19 | 1616504757072680964 |
[0,5,135,1800,19919,206964,2086746,20710806, 203834084,1997171674,19522428788,190614467420, 1860310801454,18155356377267,177224592578839, 1730651760050923,16908343191198752, 165279853754232019,1616504757072680964] |