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 | 7 |
| 5 | 21 |
| 6 | 98 |
| 7 | 392 |
| 8 | 2116 |
| 9 | 11830 |
| 10 | 70520 |
| 11 | 425240 |
| 12 | 2787810 |
| 13 | 19530213 |
| 14 | 144890639 |
| 15 | 1149978830 |
| 16 | 8558078111 |
| 17 | 76417516719 |
| 18 | 618437486332 |
| 19 | 6087770992601 |
| 20 | 54574732902278 |
| 21 | 525656554130914 |
| 22 | 5290117056157616 |
| 23 | 61626071051832409 |
| 24 | 555057889968635744 |
| 25 | 5809502058957961682 |