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 | 2 |
| 3 | 3 |
| 4 | 9 |
| 5 | 28 |
| 6 | 110 |
| 7 | 485 |
| 8 | 2358 |
| 9 | 12486 |
| 10 | 70726 |
| 11 | 425747 |
| 12 | 2702837 |
| 13 | 18004835 |
| 14 | 125337381 |
| 15 | 908737863 |
| 16 | 6843536374 |
| 17 | 53407750147 |
| 18 | 431075414218 |
| 19 | 3592384229312 |
| 20 | 30862831600689 |
| 21 | 272976843937138 |
| 22 | 2482698463801148 |
| 23 | 23192576636266041 |
| 24 | 222310388884578760 |
| 25 | 2184486850658804107 |
| 26 | 21985733344615744620 |
| 27 | 226455749821063728474 |
| 28 | 2385331864619907236147 |
| 29 | 25676170688883138634306 |
| 30 | 282253492062060457638824 |