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 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 41 |
| 5 | 155 |
| 6 | 591 |
| 7 | 2267 |
| 8 | 8735 |
| 9 | 33775 |
| 10 | 130965 |
| 11 | 509015 |
| 12 | 1982269 |
| 13 | 7732659 |
| 14 | 30208749 |
| 15 | 118167055 |
| 16 | 462760369 |
| 17 | 1814091011 |
| 18 | 7118044023 |
| 19 | 27952660883 |
| 20 | 109853552255 |
| 21 | 432021606103 |
| 22 | 1700093447847 |
| 23 | 6694137523051 |
| 24 | 26372544576331 |
| 25 | 103950885100775 |
| 26 | 409928481296331 |