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 | 1 |
| 2 | 9 |
| 3 | 187 |
| 4 | 7033 |
| 5 | 421341 |
| 6 | 37025881 |
| 7 | 4500154639 |
| 8 | 723834652017 |
| 9 | 148905928574713 |
| 10 | 38133707320119241 |
| 11 | 11894979981772431171 |
| 12 | 4439223538343665367209 |
| 13 | 1952818695816854110909717 |
| 14 | 999887879061130705615605273 |
| 15 | 589500991222520435444933020951 |