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) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 16 |
| 4 | 97 |
| 5 | 840 |
| 6 | 9751 |
| 7 | 141364 |
| 8 | 2448224 |
| 9 | 49213158 |
| 10 | 1125229242 |
| 11 | 28823071636 |
| 12 | 817379051371 |
| 13 | 25417591832210 |
| 14 | 859893812841432 |
| 15 | 31439503159778411 |
| 16 | 1235301513693182001 |
| 17 | 51906185332750116476 |
| 18 | 2322562816174820224108 |
| 19 | 110253678955674860565875 |