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 | 9 |
| 2 | 20 |
| 3 | 351 |
| 4 | 380 |
| 5 | 3249 |
| 6 | 6860 |
| 7 | 229167 |
| 8 | 118460 |
| 9 | 971919 |
| 10 | 1981100 |
| 11 | 32152941 |
| 12 | 32499740 |
| 13 | 262096389 |
| 14 | 527337740 |
| 15 | 33900692319 |
| 16 | 8503972220 |
| 17 | 68206642659 |
| 18 | 136664636780 |
| 19 | 2189507427531 |
| 20 | 2192051783900 |
| 21 | 17555075136729 |
| 22 | 35121618358220 |
| 23 | 1123425366518277 |
| 24 | 562385127902780 |