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 | 21 |
| 2 | 876 |
| 3 | 19956 |
| 4 | 528282 |
| 5 | 13706771 |
| 6 | 355281224 |
| 7 | 9248214732 |
| 8 | 240292442848 |
| 9 | 6243986963713 |
| 10 | 162252303626409 |
| 11 | 4216381439247094 |
| 12 | 109570922468132003 |
| 13 | 2847344541437365138 |
| 14 | 73992200911927723171 |
| 15 | 1922796991924326509127 |