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 | 3 |
| 3 | 7 |
| 4 | 36 |
| 5 | 130 |
| 6 | 532 |
| 7 | 2088 |
| 8 | 8304 |
| 9 | 32876 |
| 10 | 130376 |
| 11 | 516704 |
| 12 | 2048264 |
| 13 | 8118864 |
| 14 | 32182256 |
| 15 | 127565600 |
| 16 | 505652480 |
| 17 | 2004334368 |
| 18 | 7944899296 |
| 19 | 31492457536 |
| 20 | 124831656000 |
| 21 | 494815052864 |
| 22 | 1961376994048 |
| 23 | 7774621408896 |
| 24 | 30817501320448 |
| 25 | 122156223100160 |