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 | 25 |
| 3 | 111 |
| 4 | 1583 |
| 5 | 5877 |
| 6 | 118943 |
| 7 | 1239213 |
| 8 | 6500369 |
| 9 | 6228669 |
| 10 | 200696339 |
| 11 | 3293919963 |
| 12 | 125884243831 |
| 13 | 122175729021 |
| 14 | 5401896940303 |
| 15 | 121054306890369 |
| 16 | 868338554787383 |
| 17 | 848589287072283 |
| 18 | 867261322002923 |
| 19 | 24637097377492167 |