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 | 0 |
| 1 | 1 |
| 2 | 21 |
| 3 | 501 |
| 4 | 14455 |
| 5 | 496770 |
| 6 | 19911486 |
| 7 | 913839031 |
| 8 | 47303189361 |
| 9 | 2727741976785 |
| 10 | 173455231572865 |
| 11 | 12060173714421756 |
| 12 | 910301022642409476 |
| 13 | 74134150415555474881 |
| 14 | 6479678618270868170265 |
| 15 | 605042444997867941987385 |
| 16 | 60110944381660549838273911 |