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 | 5 |
| 4 | 12 |
| 5 | 41 |
| 6 | 152 |
| 7 | 685 |
| 8 | 3472 |
| 9 | 19921 |
| 10 | 126752 |
| 11 | 887765 |
| 12 | 6781632 |
| 13 | 56126201 |
| 14 | 500231552 |
| 15 | 4776869245 |
| 16 | 48656756992 |
| 17 | 526589630881 |
| 18 | 6034272215552 |
| 19 | 72989204937125 |
| 20 | 929327412759552 |
| 21 | 12424192360405961 |
| 22 | 174008703107274752 |