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) |
|---|---|
| 5 | 2 |
| 6 | 5 |
| 7 | 16 |
| 8 | 55 |
| 9 | 208 |
| 10 | 817 |
| 11 | 3336 |
| 12 | 13935 |
| 13 | 59406 |
| 14 | 257079 |
| 15 | 1126948 |
| 16 | 4992421 |
| 17 | 22318048 |
| 18 | 100546543 |
| 19 | 456055730 |
| 20 | 2080872845 |
| 21 | 9544572590 |
| 22 | 43984730855 |
| 23 | 203550840696 |
| 24 | 945562887981 |
| 25 | 4407586685688 |
| 26 | 20609668887723 |
| 27 | 96646196091276 |
| 28 | 454402001079165 |