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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 8 |
| 4 | 151 |
| 5 | 4752 |
| 6 | 214848 |
| 7 | 12915744 |
| 8 | 986580860 |
| 9 | 92994888960 |
| 10 | 10595684332288 |
| 11 | 1436363905680384 |
| 12 | 228679178713630208 |
| 13 | 42284602089642237952 |
| 14 | 8992606241049735405568 |
| 15 | 2180532527491138011131904 |
| 16 | 598191016068264518151780096 |
| 17 | 184370870332464252513762869248 |
| 18 | 63445183762362816656030378164224 |
| 19 | 24238363163428954774170892697075712 |
[1,1,8,151,4752,214848,12915744,986580860, 92994888960,10595684332288,1436363905680384, 228679178713630208,42284602089642237952, 8992606241049735405568,2180532527491138011131904, 598191016068264518151780096, 184370870332464252513762869248, 63445183762362816656030378164224, 24238363163428954774170892697075712] |