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 | 7 |
| 2 | 35 |
| 3 | 181 |
| 4 | 933 |
| 5 | 4811 |
| 6 | 24807 |
| 7 | 127913 |
| 8 | 659561 |
| 9 | 3400911 |
| 10 | 17536203 |
| 11 | 90422365 |
| 12 | 466247117 |
| 13 | 2404121747 |
| 14 | 12396433487 |
| 15 | 63920042065 |
| 16 | 329592522065 |
| 17 | 1699486218903 |
| 18 | 8763103574515 |
| 19 | 45185411569413 |
| 20 | 232990675202677 |
| 21 | 1201375684008283 |
| 22 | 6194683683674679 |
| 23 | 31941803427179001 |