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 | 6 |
| 2 | 36 |
| 3 | 84 |
| 4 | 198 |
| 5 | 462 |
| 6 | 1080 |
| 7 | 2520 |
| 8 | 5886 |
| 9 | 13746 |
| 10 | 32100 |
| 11 | 74964 |
| 12 | 175062 |
| 13 | 408822 |
| 14 | 954720 |
| 15 | 2229552 |
| 16 | 5206662 |
| 17 | 12159090 |
| 18 | 28395060 |
| 19 | 66310836 |
| 20 | 154855350 |
| 21 | 361632894 |
| 22 | 844519416 |
| 23 | 1972201800 |
| 24 | 4605672606 |
| 25 | 10755603282 |
| 26 | 25117504404 |
| 27 | 58656777396 |