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 | -3 |
| 3 | -55 |
| 4 | 3429 |
| 5 | 885137 |
| 6 | -904638963 |
| 7 | -3707218743911 |
| 8 | 60731665539301365 |
| 9 | 3980231929565571675617 |
| 10 | -1043385959026442521712292579 |
| 11 | -1094071562179856506263860787078039 |