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 | 7616 |
| 5 | 5141250 |
| 6 | 552093440 |
| 7 | 20631905875 |
| 8 | 395001645696 |
| 9 | 4771909547076 |
| 10 | 41190314035200 |
| 11 | 275192443300005 |
| 12 | 1502690499112000 |
| 13 | 6971521964029766 |
| 14 | 28275884687022336 |
| 15 | 102456840191225975 |
| 16 | 337289521082456320 |
| 17 | 1022310183284613000 |
| 18 | 2883605488481550336 |
| 19 | 7636012822945480521 |