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 | 3 |
| 1 | 16 |
| 2 | 30 |
| 3 | 72 |
| 4 | 178 |
| 5 | 444 |
| 6 | 1114 |
| 7 | 2808 |
| 8 | 7098 |
| 9 | 17984 |
| 10 | 45656 |
| 11 | 116106 |
| 12 | 295718 |
| 13 | 754226 |
| 14 | 1926060 |
| 15 | 4924188 |
| 16 | 12602416 |
| 17 | 32284214 |
| 18 | 82777240 |
| 19 | 212415744 |
| 20 | 545495716 |
| 21 | 1401849594 |
| 22 | 3604921774 |
| 23 | 9275890122 |
| 24 | 23881602058 |
| 25 | 61518226734 |
| 26 | 158548607640 |
| 27 | 408814563524 |
| 28 | 1054590179342 |