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 | 0 |
| 2 | 5 |
| 3 | 71 |
| 4 | 1625 |
| 5 | 48699 |
| 6 | 1815157 |
| 7 | 80960200 |
| 8 | 4205895521 |
| 9 | 249447427145 |
| 10 | 16631893722851 |
| 11 | 1231521399730489 |
| 12 | 100270564101729529 |
| 13 | 8903719880410535595 |
| 14 | 856322102196977446955 |
| 15 | 88677383473792696758599 |
| 16 | 9837660365763014667911553 |
| 17 | 1163993530309417488368300653 |