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 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 13 |
| 6 | 34 |
| 7 | 84 |
| 8 | 270 |
| 9 | 912 |
| 10 | 3755 |
| 11 | 17169 |
| 12 | 90953 |
| 13 | 538858 |
| 14 | 3586559 |
| 15 | 26459702 |
| 16 | 215517278 |
| 17 | 1925402918 |
| 18 | 18785105127 |
| 19 | 199301164172 |