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 | 4 |
| 3 | 11 |
| 4 | 41 |
| 5 | 139 |
| 6 | 515 |
| 7 | 1871 |
| 8 | 7004 |
| 9 | 26191 |
| 10 | 99137 |
| 11 | 376300 |
| 12 | 1437105 |
| 13 | 5505203 |
| 14 | 21167781 |
| 15 | 81602665 |
| 16 | 315395985 |
| 17 | 1221558683 |
| 18 | 4740410605 |
| 19 | 18426590090 |
| 20 | 71736136773 |
| 21 | 279654633032 |
| 22 | 1091552835344 |
| 23 | 4265355947434 |
| 24 | 16684466516559 |