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 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 7 |
| 5 | 23 |
| 6 | 100 |
| 7 | 333 |
| 8 | 1443 |
| 9 | 6910 |
| 10 | 36035 |
| 11 | 186958 |
| 12 | 1095251 |
| 13 | 6620976 |
| 14 | 42151463 |
| 15 | 290483173 |
| 16 | 2030271491 |
| 17 | 15044953241 |
| 18 | 116044969497 |
| 19 | 930056879535 |
| 20 | 7749440529803 |
| 21 | 66931578540965 |
| 22 | 597728811956244 |
| 23 | 5511695171795434 |
| 24 | 52578231393128128 |
| 25 | 515775207055816041 |