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 | 3 |
| 2 | 18 |
| 3 | 144 |
| 4 | 1422 |
| 5 | 16848 |
| 6 | 235458 |
| 7 | 3827628 |
| 8 | 71466174 |
| 9 | 1515031920 |
| 10 | 36091609434 |
| 11 | 957367079244 |
| 12 | 28050237910926 |
| 13 | 901359663633000 |
| 14 | 31567805908329330 |
| 15 | 1198307340146774844 |
| 16 | 49060139971072916142 |
| 17 | 2156816501291429473248 |