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 | 3 |
| 2 | 20 |
| 3 | 68 |
| 4 | 225 |
| 5 | 627 |
| 6 | 2152 |
| 7 | 7036 |
| 8 | 22392 |
| 9 | 74381 |
| 10 | 241819 |
| 11 | 793240 |
| 12 | 2604908 |
| 13 | 8530131 |
| 14 | 28013101 |
| 15 | 91893580 |
| 16 | 301557767 |
| 17 | 989945590 |
| 18 | 3248890744 |
| 19 | 10664829792 |
| 20 | 35007809686 |
| 21 | 114914687393 |
| 22 | 377229380984 |
| 23 | 1238309771635 |
| 24 | 4064987753276 |