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 | 3 |
| 2 | 21 |
| 3 | 99 |
| 4 | 375 |
| 5 | 1137 |
| 6 | 3267 |
| 7 | 8595 |
| 8 | 21891 |
| 9 | 52965 |
| 10 | 120087 |
| 11 | 267843 |
| 12 | 572145 |
| 13 | 1194483 |
| 14 | 2476743 |
| 15 | 5037825 |
| 16 | 9980691 |