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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 10 |
| 4 | 64 |
| 5 | 704 |
| 6 | 8704 |
| 7 | 160768 |
| 8 | 3146240 |
| 9 | 85459456 |
| 10 | 2379068416 |
| 11 | 87838524416 |
| 12 | 3254378586112 |
| 13 | 155039348776960 |
| 14 | 7304909102465024 |
| 15 | 432732882146443264 |
| 16 | 25086801102965899264 |
| 17 | 1797560686374797508608 |
| 18 | 125049014505246260592640 |
[1,1,2,10,64,704,8704,160768,3146240,85459456, 2379068416,87838524416,3254378586112, 155039348776960,7304909102465024, 432732882146443264,25086801102965899264, 1797560686374797508608,125049014505246260592640] |