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 | 2 |
| 2 | 0 |
| 3 | 8 |
| 4 | 96 |
| 5 | 1248 |
| 6 | 18176 |
| 7 | 295040 |
| 8 | 5294592 |
| 9 | 104269312 |
| 10 | 2239225856 |
| 11 | 52150118400 |
| 12 | 1310675066880 |
| 13 | 35390943453184 |
| 14 | 1022570290544640 |
| 15 | 31498715705147392 |
| 16 | 1030904079324413952 |
| 17 | 35736902010299351040 |
| 18 | 1308417934560279396352 |