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 | 3 |
| 3 | 12 |
| 4 | 52 |
| 5 | 232 |
| 6 | 1049 |
| 7 | 4777 |
| 8 | 21845 |
| 9 | 100159 |
| 10 | 460023 |
| 11 | 2115350 |
| 12 | 9735205 |
| 13 | 44829766 |
| 14 | 206526972 |
| 15 | 951759621 |
| 16 | 4387156587 |
| 17 | 20226421380 |
| 18 | 93264500832 |
| 19 | 430091815527 |
| 20 | 1983549213861 |
| 21 | 9148582037193 |
| 22 | 42197572190160 |
| 23 | 194643215702835 |