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 | 2 |
| 2 | 11 |
| 3 | 110 |
| 4 | 1555 |
| 5 | 28248 |
| 6 | 626219 |
| 7 | 16383796 |
| 8 | 494052001 |
| 9 | 16870035070 |
| 10 | 643387631279 |
| 11 | 27105962133498 |
| 12 | 1250204513874499 |
| 13 | 62655598615243340 |
| 14 | 3390311968553510615 |
| 15 | 196993431796981792712 |
| 16 | 12233255754813946704001 |
| 17 | 808560048188371962179034 |
| 18 | 56672826844096496885966099 |