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 | 11 |
| 5 | 27 |
| 6 | 65 |
| 7 | 164 |
| 8 | 417 |
| 9 | 1068 |
| 10 | 2756 |
| 11 | 7148 |
| 12 | 18614 |
| 13 | 48639 |
| 14 | 127464 |
| 15 | 334865 |
| 16 | 881658 |
| 17 | 2325751 |
| 18 | 6145597 |
| 19 | 16263867 |
| 20 | 43099805 |
| 21 | 114356612 |
| 22 | 303761261 |
| 23 | 807692035 |
| 24 | 2149632062 |
| 25 | 5726042116 |
| 26 | 15264691108 |
| 27 | 40722913455 |
| 28 | 108713644517 |