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 | 1 |
| 2 | -60 |
| 3 | -721 |
| 4 | -4080 |
| 5 | -15593 |
| 6 | -46592 |
| 7 | -117521 |
| 8 | -261888 |
| 9 | -530929 |
| 10 | -998976 |
| 11 | -1769513 |
| 12 | -2981888 |
| 13 | -4818617 |
| 14 | -7513152 |
| 15 | -11357857 |
| 16 | -16711680 |
| 17 | -24006497 |
| 18 | -33750080 |
| 19 | -46521593 |
| 20 | -62951424 |
| 21 | -83668969 |
| 22 | -109185600 |
| 23 | -139647281 |
| 24 | -174325760 |
| 25 | -210586193 |
| 26 | -241806912 |