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 | 6 |
| 3 | 81 |
| 4 | 276 |
| 5 | 1056 |
| 6 | 1381 |
| 7 | 6906 |
| 8 | 17956 |
| 9 | 34531 |
| 10 | 40056 |
| 11 | 200281 |
| 12 | 520731 |
| 13 | 1001406 |
| 14 | 1482081 |
| 15 | 7410406 |
| 16 | 19267056 |
| 17 | 37052031 |
| 18 | 60765331 |
| 19 | 303826656 |
| 20 | 789949306 |
| 21 | 1519133281 |
| 22 | 3220562556 |
| 23 | 13429138206 |
| 24 | 16102812781 |
| 25 | 41867313231 |
| 26 | 80514063906 |
| 27 | 196454315931 |
| 28 | 711744324931 |