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) |
|---|---|
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 1 |
| 8 | 9 |
| 9 | 27 |
| 10 | 15 |
| 11 | 18 |
| 12 | 288 |
| 13 | 288 |
| 14 | 420 |
| 15 | 464 |
| 16 | 1856 |
| 17 | 10080 |
| 18 | 46848 |
| 19 | 210240 |
| 20 | 400320 |
| 21 | 652848 |
| 22 | 3991680 |
| 23 | 27528402 |
| 24 | 32659200 |
| 25 | 163296000 |
| 26 | 1143463200 |
| 27 | 1305467240 |
| 28 | 6840489600 |
| 29 | 9453465438 |
| 30 | 337082683248 |
| 31 | 163425485250 |
| 32 | 8376514506360 |
| 33 | 8440230839040 |
| 34 | 5088099594240 |