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 | 7 |
| 3 | 15652 |
| 4 | 4466072310336 |
| 5 | 257010442859540072735404130304 |
| 6 | 12039114411811108434329752218564963041089979745446343475200 |