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 | 3 |
| 3 | 9 |
| 4 | 28 |
| 5 | 91 |
| 6 | 307 |
| 7 | 1067 |
| 8 | 3792 |
| 9 | 13702 |
| 10 | 50148 |
| 11 | 185416 |
| 12 | 691277 |
| 13 | 2595167 |
| 14 | 9800041 |
| 15 | 37194707 |
| 16 | 141787644 |
| 17 | 542583488 |
| 18 | 2083404030 |
| 19 | 8024142706 |
| 20 | 30988922366 |
| 21 | 119972435149 |
| 22 | 465505007827 |
| 23 | 1809877343351 |
| 24 | 7049866113619 |
| 25 | 27507668129630 |