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 | 21 |
| 3 | 303 |
| 4 | 7581 |
| 5 | 291903 |
| 6 | 16004541 |
| 7 | 11842303 |
| 8 | 113649275901 |
| 9 | 13729560793503 |
| 10 | 2038432934681661 |
| 11 | 364819653173167503 |
| 12 | 77453921498088781821 |
| 13 | 19245815560568454066303 |
| 14 | 5532998260944453966936381 |