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) |
|---|---|
| 4 | 30 |
| 5 | 2206 |
| 6 | 56242 |
| 7 | 766198 |
| 8 | 7056249 |
| 9 | 49662920 |
| 10 | 286860862 |
| 11 | 1422695104 |
| 12 | 6246302316 |
| 13 | 24810260818 |
| 14 | 90593318410 |
| 15 | 307833736038 |
| 16 | 982717917851 |
| 17 | 2969842897554 |
| 18 | 8548862507642 |
| 19 | 23559234462890 |
| 20 | 62421788882924 |
| 21 | 159585012804848 |
| 22 | 394875247007432 |
| 23 | 948171537489016 |