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 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 20 |
| 7 | 51 |
| 8 | 121 |
| 9 | 321 |
| 10 | 826 |
| 11 | 2186 |
| 12 | 5789 |
| 13 | 16114 |
| 14 | 42449 |
| 15 | 118281 |
| 16 | 328425 |
| 17 | 908933 |
| 18 | 2510553 |
| 19 | 7138324 |
| 20 | 19869748 |