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 | -21 |
| 2 | 518 |
| 3 | -16086 |
| 4 | 619455 |
| 5 | -28997507 |
| 6 | 1621813676 |
| 7 | -106810679196 |
| 8 | 8181571662285 |
| 9 | -721200878840225 |
| 10 | 72488343299017506 |
| 11 | -8240646522324583186 |
| 12 | 1052039595125648117163 |
| 13 | -149871019205601062538351 |
| 14 | 23688770132969478817542760 |
| 15 | -4133100022172241089923256632 |