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 | 5 |
| 5 | 11 |
| 6 | 38 |
| 7 | 122 |
| 8 | 496 |
| 9 | 2005 |
| 10 | 8707 |
| 11 | 38364 |
| 12 | 173562 |
| 13 | 792827 |
| 14 | 3662800 |
| 15 | 17034367 |
| 16 | 79702578 |
| 17 | 374624253 |
| 18 | 1767881397 |
| 19 | 8370666416 |
| 20 | 39751064122 |
| 21 | 189262621739 |
| 22 | 903220020390 |
| 23 | 4319518316898 |
| 24 | 20697040024784 |