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 | 1 |
| 2 | 9 |
| 3 | 25 |
| 4 | 57 |
| 5 | 121 |
| 6 | 633 |
| 7 | 1657 |
| 8 | 3705 |
| 9 | 7801 |
| 10 | 40569 |
| 11 | 106105 |
| 12 | 237177 |
| 13 | 499321 |
| 14 | 2596473 |
| 15 | 6790777 |
| 16 | 15179385 |
| 17 | 31956601 |
| 18 | 166174329 |
| 19 | 434609785 |
| 20 | 971480697 |
| 21 | 2045222521 |
| 22 | 10635157113 |
| 23 | 27815026297 |
| 24 | 62174764665 |
| 25 | 130894241401 |
| 26 | 680650055289 |