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| n | a(n) |
|---|---|
| 1 | 180 |
| 2 | 1232 |
| 3 | 5680 |
| 4 | 38332 |
| 5 | 185620 |
| 6 | 1215600 |
| 7 | 6080510 |
| 8 | 38748690 |
| 9 | 198765264 |
| 10 | 1238605998 |
| 11 | 6482518286 |
| 12 | 39672453450 |
| 13 | 211010740516 |
| 14 | 1272735272854 |
| 15 | 6857786261434 |
| 16 | 40883144370828 |
| 17 | 222596116574864 |
| 18 | 1314621503491854 |
[180,1232,5680,38332,185620,1215600,6080510, 38748690,198765264,1238605998,6482518286, 39672453450,211010740516,1272735272854, 6857786261434,40883144370828,222596116574864, 1314621503491854] |