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 | 4 |
| 3 | 12 |
| 4 | 34 |
| 5 | 94 |
| 6 | 258 |
| 7 | 706 |
| 8 | 1930 |
| 9 | 5274 |
| 10 | 14410 |
| 11 | 39370 |
| 12 | 107562 |
| 13 | 293866 |
| 14 | 802858 |
| 15 | 2193450 |
| 16 | 5992618 |
| 17 | 16372138 |
| 18 | 44729514 |
| 19 | 122203306 |
| 20 | 333865642 |
| 21 | 912137898 |
| 22 | 2492007082 |
| 23 | 6808289962 |
| 24 | 18600594090 |
| 25 | 50817768106 |
| 26 | 138836724394 |
| 27 | 379308985002 |
| 28 | 1036291418794 |
| 29 | 2831200807594 |