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 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 3 |
| 6 | 12 |
| 7 | 24 |
| 8 | 103 |
| 9 | 387 |
| 10 | 1819 |
| 11 | 8933 |
| 12 | 48632 |
| 13 | 279484 |
| 14 | 1716523 |
| 15 | 11126025 |
| 16 | 76014437 |
| 17 | 544945399 |
| 18 | 4089010392 |
| 19 | 32025053060 |
| 20 | 261213946739 |
| 21 | 2214280580389 |
| 22 | 19471365925297 |
| 23 | 177319383231697 |
| 24 | 1669735890602062 |
| 25 | 16235408370162588 |
| 26 | 162796351456044465 |
| 27 | 1681427459283678177 |