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 | 5 |
| 2 | 21 |
| 3 | 69 |
| 4 | 309 |
| 5 | 1077 |
| 6 | 4661 |
| 7 | 19173 |
| 8 | 74917 |
| 9 | 310285 |
| 10 | 1234813 |
| 11 | 4909789 |
| 12 | 19434725 |
| 13 | 76878941 |
| 14 | 304281693 |
| 15 | 1205650205 |