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 | 4 |
| 3 | 19 |
| 4 | 100 |
| 5 | 581 |
| 6 | 3912 |
| 7 | 28091 |
| 8 | 211700 |
| 9 | 1655601 |
| 10 | 13286320 |
| 11 | 109058381 |
| 12 | 911436949 |
| 13 | 7731247492 |