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 | 3 |
| 3 | 9 |
| 4 | 29 |
| 5 | 97 |
| 6 | 336 |
| 7 | 1188 |
| 8 | 4275 |
| 9 | 15579 |
| 10 | 57358 |
| 11 | 212908 |
| 12 | 795657 |
| 13 | 2990221 |
| 14 | 11291665 |
| 15 | 42814783 |
| 16 | 162920417 |
| 17 | 621885767 |
| 18 | 2380348729 |