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 | 7 |
| 3 | 36 |
| 4 | 297 |
| 5 | 2905 |
| 6 | 39083 |
| 7 | 603698 |
| 8 | 11637502 |
| 9 | 288086265 |
| 10 | 7728273214 |
| 11 | 251460107734 |
| 12 | 9155428058351 |
| 13 | 353182833587645 |
| 14 | 15035130777416118 |
| 15 | 726840450530910033 |
| 16 | 39326730322451969003 |
| 17 | 2211193504550790268932 |
| 18 | 137315317472893091758587 |