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 | 1 |
| 1 | 20 |
| 2 | 400 |
| 3 | 8902 |
| 4 | 197742 |
| 5 | 4897256 |
| 6 | 120921506 |
| 7 | 3284294545 |
| 8 | 88867026005 |