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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 10 |
| 4 | 64 |
| 5 | 596 |
| 6 | 8056 |
| 7 | 130432 |
| 8 | 2534960 |
| 9 | 59822884 |
| 10 | 1718480368 |
| 11 | 56754444440 |
| 12 | 2110577206816 |
| 13 | 87981286785328 |
| 14 | 4129351961475872 |
| 15 | 218382856010529472 |
| 16 | 12813477368159567200 |
| 17 | 822337333595479929044 |
| 18 | 57213666993723455063392 |
| 19 | 4305630141314873304140008 |
[1,1,2,10,64,596,8056,130432,2534960,59822884, 1718480368,56754444440,2110577206816, 87981286785328,4129351961475872, 218382856010529472,12813477368159567200, 822337333595479929044,57213666993723455063392, 4305630141314873304140008] |