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) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 23 |
| 6 | 104 |
| 7 | 531 |
| 8 | 2982 |
| 9 | 18109 |
| 10 | 117545 |
| 11 | 808764 |
| 12 | 5862253 |
| 13 | 44553224 |
| 14 | 353713232 |
| 15 | 2924697019 |
| 16 | 25124481690 |
| 17 | 223768976093 |
| 18 | 2062614190733 |
| 19 | 19646231085928 |
| 20 | 193102738376890 |
| 21 | 1956191484175505 |
| 22 | 20401540100814142 |
| 23 | 218825717967033373 |
| 24 | 2411606083999341827 |