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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 6 |
| 5 | 34 |
| 6 | 194 |
| 7 | 1275 |
| 8 | 10196 |
| 9 | 99916 |
| 10 | 1164684 |
| 11 | 15912733 |
| 12 | 250678314 |
| 13 | 4507337214 |
| 14 | 91329638814 |
| 15 | 2069998845799 |
| 16 | 52044680125128 |
| 17 | 1443501036281272 |
| 18 | 43878538143611192 |
| 19 | 1455221004684341721 |
| 20 | 52393847060853213806 |
| 21 | 2040530475078456780538 |
| 22 | 85617882485110184661402 |