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 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 28 |
| 5 | 62 |
| 6 | 571 |
| 7 | 1555 |
| 8 | 2012 |
| 9 | 2529 |
| 10 | 2759 |
| 11 | 3018 |
| 12 | 4158 |
| 13 | 4740 |
| 14 | 6819 |
| 15 | 10564 |
| 16 | 11665 |
| 17 | 32858 |
| 18 | 139892 |
| 19 | 392129 |
| 20 | 707969 |
| 21 | 1049721 |
| 22 | 2081164 |
| 23 | 14990403 |
| 24 | 36112275 |
| 25 | 39552834 |
| 26 | 42710786 |
| 27 | 199618805 |