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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 1 |
| 6 | -25 |
| 7 | 85 |
| 8 | -205 |
| 9 | 415 |
| 10 | -751 |
| 11 | 13351 |
| 12 | -74551 |
| 13 | 277501 |
| 14 | -825301 |
| 15 | 2114017 |
| 16 | -31272601 |
| 17 | 234796831 |
| 18 | -1167200191 |
| 19 | 4534428271 |
| 20 | -14884655503 |
| 21 | 196703557717 |
| 22 | -1802713881757 |
| 23 | 11116971405937 |
| 24 | -53015088629977 |
| 25 | 211179438004855 |
| 26 | -2599947442920103 |
| 27 | 27477399011166703 |
| 28 | -200902152943783903 |
[0,1,-1,1,-1,1,-25,85,-205,415,-751,13351,-74551, 277501,-825301,2114017,-31272601,234796831, -1167200191,4534428271,-14884655503,196703557717, -1802713881757,11116971405937,-53015088629977, 211179438004855,-2599947442920103, 27477399011166703,-200902152943783903] |