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 | -3 |
| 2 | 8 |
| 3 | -23 |
| 4 | 74 |
| 5 | -262 |
| 6 | 993 |
| 7 | -3943 |
| 8 | 16178 |
| 9 | -68000 |
| 10 | 291191 |
| 11 | -1265618 |
| 12 | 5568263 |
| 13 | -24749363 |
| 14 | 110961248 |
| 15 | -501209303 |
| 16 | 2278704938 |
| 17 | -10419244888 |
| 18 | 47882934663 |
| 19 | -221047167628 |
| 20 | 1024586641973 |
| 21 | -4766517165713 |
| 22 | 22248226873538 |
| 23 | -104160733650738 |
| 24 | 489007907489239 |