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 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 8 |
| 4 | 5 |
| 5 | -220 |
| 6 | 1895 |
| 7 | -9140 |
| 8 | -302175 |
| 9 | -2778300 |
| 10 | -95631825 |
| 11 | -10071428100 |
| 12 | -236788407375 |
| 13 | 57706241794500 |
| 14 | -7412904844112625 |
| 15 | 525300693117661500 |
| 16 | 348922898045520800625 |
| 17 | 55166584329677385922500 |
| 18 | 28368558145043150339199375 |
| 19 | 46873210124734003815040957500 |