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 | 4 |
| 3 | 27 |
| 4 | 257 |
| 5 | 3133 |
| 6 | 46737 |
| 7 | 824567 |
| 8 | 16792845 |
| 9 | 387700506 |
| 10 | 10005766337 |
| 11 | 285445919589 |
| 12 | 8919587932524 |
| 13 | 302975123887680 |
| 14 | 11115145723728035 |
| 15 | 438000897534309171 |
| 16 | 18450681900124075166 |
| 17 | 827395845674975999727 |
| 18 | 39352977072147424071861 |