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) |
|---|---|
| 1 | 0 |
| 2 | -1 |
| 3 | 118 |
| 4 | 13983 |
| 5 | 1894076 |
| 6 | 361025495 |
| 7 | 96826261890 |
| 8 | 35181809198207 |
| 9 | 16677063111790072 |
| 10 | 9999993868933742199 |
| 11 | 7400249593980659558990 |
| 12 | 6624737245034612579099807 |
| 13 | 7056410013376700546645974068 |