This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -5 |
| 3 | -155 |
| 4 | 28675 |
| 5 | 31857925 |
| 6 | -212333070125 |
| 7 | -8491411807368875 |
| 8 | 2037471806119124711875 |
| 9 | 2933289072587326393069793125 |
| 10 | -25337824341236140066496699758578125 |
| 11 | -1313212585969062194023540996089250607796875 |
| 12 | 408368279891017634352398087776483543777178681171875 |