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 | 0 |
| 2 | 5 |
| 3 | 34 |
| 4 | 144 |
| 5 | 490 |
| 6 | 1470 |
| 7 | 3990 |
| 8 | 10045 |
| 9 | 23750 |
| 10 | 53205 |
| 11 | 113694 |
| 12 | 233039 |
| 13 | 460096 |
| 14 | 878269 |
| 15 | 1626034 |