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 | 27 |
| 5 | 190 |
| 6 | 1621 |
| 7 | 17271 |
| 8 | 200536 |
| 9 | 2757881 |
| 10 | 47108763 |
| 11 | 843069901 |
| 12 | 17797435824 |