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 | 15 |
| 3 | 16 |
| 4 | 239 |
| 5 | 255 |
| 6 | 3809 |
| 7 | 4064 |
| 8 | 60705 |
| 9 | 64769 |
| 10 | 967471 |
| 11 | 1032240 |
| 12 | 15418831 |
| 13 | 16451071 |
| 14 | 245733825 |
| 15 | 262184896 |
| 16 | 3916322369 |
| 17 | 4178507265 |
| 18 | 62415424079 |
| 19 | 66593931344 |
| 20 | 994730462895 |
| 21 | 1061324394239 |
| 22 | 15853271982241 |