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 | 10 |
| 3 | 135 |
| 4 | 1980 |
| 5 | 30475 |
| 6 | 483702 |
| 7 | 7847525 |
| 8 | 129419240 |
| 9 | 2161766520 |
| 10 | 36481155310 |
| 11 | 620845213890 |
| 12 | 10640356142700 |
| 13 | 183453873965570 |
| 14 | 3179310190998270 |
| 15 | 55345614317169210 |