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) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | -810 |
| 3 | -22134 |
| 4 | -278634 |
| 5 | -2122524 |
| 6 | -11039814 |
| 7 | -43693008 |
| 8 | -145572714 |
| 9 | -424326378 |
| 10 | -1083745980 |
| 11 | -2551211640 |
| 12 | -5663429382 |
| 13 | -11474793708 |
| 14 | -22397094864 |
| 15 | -42109347204 |
| 16 | -74498070378 |
| 17 | -128307428244 |
| 18 | -217704941082 |
| 19 | -349133308872 |
| 20 | -555058873404 |
| 21 | -870035772336 |
| 22 | -1308777310008 |