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 | 2 |
| 3 | 7 |
| 4 | 24 |
| 5 | 86 |
| 6 | 314 |
| 7 | 1163 |
| 8 | 4352 |
| 9 | 16414 |
| 10 | 62292 |
| 11 | 237590 |
| 12 | 909960 |
| 13 | 3497248 |
| 14 | 13480826 |
| 15 | 52097267 |
| 16 | 201780224 |
| 17 | 783051638 |
| 18 | 3044061116 |
| 19 | 11851853042 |
| 20 | 46208337584 |
| 21 | 180383564228 |
| 22 | 704961896036 |
| 23 | 2757926215742 |
| 24 | 10799653176704 |
| 25 | 42326626862636 |
| 26 | 166021623024584 |
| 27 | 651683311373788 |