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 | 23 |
| 3 | 192 |
| 4 | 1687 |
| 5 | 15253 |
| 6 | 140504 |
| 7 | 1311292 |
| 8 | 12357015 |
| 9 | 117318162 |
| 10 | 1120436273 |
| 11 | 10752242592 |
| 12 | 103596191608 |
| 13 | 1001494496863 |
| 14 | 9709576926716 |
| 15 | 94369011385192 |
| 16 | 919175964169623 |
| 17 | 8970063281146830 |
| 18 | 87685232945278010 |
| 19 | 858446087522807784 |
| 20 | 8415669293820893937 |