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 | 16 |
| 2 | 65 |
| 3 | 45 |
| 4 | -116 |
| 5 | 340 |
| 6 | -1240 |
| 7 | 5480 |
| 8 | -28464 |
| 9 | 169248 |
| 10 | -1125840 |
| 11 | 8197680 |
| 12 | -63806016 |
| 13 | 514314240 |
| 14 | -4058967744 |
| 15 | 26952984000 |
| 16 | -37203513984 |
| 17 | -4251686488704 |
| 18 | 140692872720384 |
| 19 | -3560137793538048 |
| 20 | 84004474130786304 |
| 21 | -1955196907518928896 |
| 22 | 45927815909901004800 |