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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 25 |
| 3 | 143 |
| 4 | 1598 |
| 5 | 10627 |
| 6 | 194220 |
| 7 | 26399 |
| 8 | 37811757 |
| 9 | 15689797 |
| 10 | 1609719151 |
| 11 | 42001126081 |
| 12 | 42116737194 |
| 13 | 2277292670319 |
| 14 | 8475536580225 |
| 15 | 57483036385216 |
| 16 | 1185808703658960 |
| 17 | 2800250032195382 |
| 18 | 203292337502775829 |
| 19 | 294180235677139843 |
| 20 | 28666496154250702728 |
[1,25,143,1598,10627,194220,26399,37811757, 15689797,1609719151,42001126081,42116737194, 2277292670319,8475536580225,57483036385216, 1185808703658960,2800250032195382, 203292337502775829,294180235677139843, 28666496154250702728] |