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) |
|---|---|
| 3 | 1 |
| 4 | 6 |
| 5 | 25 |
| 6 | 80 |
| 7 | 91 |
| 8 | -1694 |
| 9 | -22875 |
| 10 | -193740 |
| 11 | -1119569 |
| 12 | -768394 |
| 13 | 101162425 |
| 14 | 1930987240 |
| 15 | 23583202371 |
| 16 | 181575384906 |
| 17 | -306743537075 |
| 18 | -45405986594980 |
| 19 | -1070132302146089 |
| 20 | -16439720013909794 |
| 21 | -145808623945689375 |
| 22 | 1048196472097011600 |
| 23 | 84226169502099763051 |