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 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 16 |
| 6 | 50 |
| 7 | 150 |
| 8 | 458 |
| 9 | 1388 |
| 10 | 4233 |
| 11 | 12875 |
| 12 | 39227 |
| 13 | 119456 |
| 14 | 363868 |
| 15 | 1107912 |
| 16 | 3372793 |
| 17 | 10264156 |
| 18 | 31228969 |