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) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 18 |
| 5 | 80 |
| 6 | 196 |
| 7 | 554 |
| 8 | 1824 |
| 9 | 2292 |
| 10 | 7218 |
| 11 | 45522 |
| 12 | 288135 |
| 13 | 660113 |
| 14 | 3201130 |
| 15 | 10512530 |
| 16 | 17675063 |
| 17 | 191230544 |
| 18 | 207521990 |