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 | 7 |
| 2 | 34 |
| 3 | 143 |
| 4 | 560 |
| 5 | 2108 |
| 6 | 7752 |
| 7 | 28101 |
| 8 | 100947 |
| 9 | 360526 |
| 10 | 1282735 |
| 11 | 4552624 |
| 12 | 16131656 |
| 13 | 57099056 |
| 14 | 201962057 |
| 15 | 714012495 |
| 16 | 2523515514 |
| 17 | 8916942687 |
| 18 | 31504028992 |
| 19 | 111295205284 |
| 20 | 393151913464 |
| 21 | 1388758662221 |
| 22 | 4905479957435 |
| 23 | 17327203698086 |
| 24 | 61202661233823 |
| 25 | 216176614077600 |