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 | 9 |
| 3 | 56 |
| 4 | 1419 |
| 5 | 107655 |
| 6 | 23325250 |
| 7 | 14991391782 |
| 8 | 27504159228709 |
| 9 | 145843735771766573 |