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 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 11 |
| 6 | 25 |
| 7 | 55 |
| 8 | 129 |
| 9 | 303 |
| 10 | 721 |
| 11 | 1743 |
| 12 | 4241 |
| 13 | 10415 |
| 14 | 25761 |
| 15 | 64095 |
| 16 | 160385 |
| 17 | 403263 |
| 18 | 1018369 |
| 19 | 2581887 |
| 20 | 6569089 |
| 21 | 16767871 |
| 22 | 42927105 |
| 23 | 110194175 |
| 24 | 283574017 |
| 25 | 731427583 |
| 26 | 1890600193 |
| 27 | 4896499455 |
| 28 | 12704869633 |
| 29 | 33021750015 |
| 30 | 85966113281 |