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 | 9 |
| 3 | 49 |
| 4 | 57 |
| 5 | 2401 |
| 6 | -9063 |
| 7 | -153502 |
| 8 | -755943 |
| 9 | -767039 |
| 10 | -40127031 |
| 11 | -58813391 |
| 12 | -1696965207 |
| 13 | -4483997699 |
| 14 | 105920054242 |
| 15 | -203398909151 |
| 16 | 555306094297 |
| 17 | -2817291378419 |
| 18 | 5514657953337 |
| 19 | 442400619060589 |
| 20 | -739096098204743 |
| 21 | -69507309377825326 |
| 22 | -90124818751960951 |