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 | 4 |
| 4 | 10 |
| 5 | 31 |
| 6 | 100 |
| 7 | 330 |
| 8 | 1093 |
| 9 | 3628 |
| 10 | 12049 |
| 11 | 40023 |
| 12 | 132951 |
| 13 | 441651 |
| 14 | 1467130 |
| 15 | 4873698 |
| 16 | 16190071 |
| 17 | 53782249 |
| 18 | 178660761 |
| 19 | 593498199 |
| 20 | 1971558339 |