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 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 50 |
| 6 | 288 |
| 7 | 2450 |
| 8 | 16384 |
| 9 | 62208 |
| 10 | 233600 |
| 11 | 638880 |
| 12 | 1755072 |
| 13 | 3901534 |
| 14 | 8772176 |
| 15 | 17051850 |
| 16 | 33507328 |
| 17 | 59175640 |
| 18 | 105557904 |
| 19 | 173570244 |
| 20 | 287904000 |
| 21 | 447885774 |
| 22 | 702042000 |
| 23 | 1044894554 |
| 24 | 1565385984 |
| 25 | 2247132500 |
| 26 | 3244194304 |
| 27 | 4519015596 |