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 | 7 |
| 3 | 19 |
| 4 | 103 |
| 5 | 341 |
| 6 | 1809 |
| 7 | 6336 |
| 8 | 33899 |
| 9 | 121483 |
| 10 | 656199 |
| 11 | 2381512 |
| 12 | 12957809 |
| 13 | 47419503 |
| 14 | 259395664 |
| 15 | 954961034 |
| 16 | 5245001951 |
| 17 | 19397198595 |
| 18 | 106871608053 |