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) |
|---|---|
| 1 | 1 |
| 2 | -3 |
| 3 | 28 |
| 4 | -707 |
| 5 | 44576 |
| 6 | -6695766 |
| 7 | 2324916672 |
| 8 | -1827405843363 |
| 9 | 3201960457239040 |
| 10 | -12360766887879809858 |
| 11 | 104155804285010077051904 |
| 12 | -1901288103716422362163490318 |
| 13 | 74716157012390526276910403768320 |
| 14 | -6287554722733254962685763077329845772 |
| 15 | 1127914878748595440161120152354758317867008 |