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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | -1 |
| 4 | -7 |
| 5 | 25 |
| 6 | 265 |
| 7 | -1705 |
| 8 | -24175 |
| 9 | 227665 |
| 10 | 4037425 |
| 11 | -50333425 |
| 12 | -1070526775 |
| 13 | 16655398825 |
| 14 | 412826556025 |
| 15 | -7711225809625 |
| 16 | -218150106913375 |
| 17 | 4760499335502625 |
| 18 | 151297155973926625 |
| 19 | -3779764853639958625 |
| 20 | -133288452772763494375 |
| 21 | 3752942823715824285625 |
| 22 | 145378048431548466795625 |
| 23 | -4556465805050372544735625 |
| 24 | -192296944484564858674279375 |
| 25 | 6641455313355871353308640625 |
[1,1,1,-1,-7,25,265,-1705,-24175,227665,4037425, -50333425,-1070526775,16655398825,412826556025, -7711225809625,-218150106913375,4760499335502625, 151297155973926625,-3779764853639958625, -133288452772763494375,3752942823715824285625, 145378048431548466795625, -4556465805050372544735625, -192296944484564858674279375, 6641455313355871353308640625] |