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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 26 |
| 4 | 105 |
| 5 | 526 |
| 6 | 3157 |
| 7 | 22100 |
| 8 | 176801 |
| 9 | 1591210 |
| 10 | 15912101 |
| 11 | 175033112 |
| 12 | 2100397345 |
| 13 | 27305165486 |
| 14 | 382272316805 |
| 15 | 5734084752076 |
| 16 | 91745356033217 |
| 17 | 1559671052564690 |
| 18 | 28074078946164421 |
| 19 | 533407499977124000 |
| 20 | 10668149999542480001 |
[1,8,26,105,526,3157,22100,176801,1591210, 15912101,175033112,2100397345,27305165486, 382272316805,5734084752076,91745356033217, 1559671052564690,28074078946164421, 533407499977124000,10668149999542480001] |