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 | 35 |
| 3 | -217 |
| 4 | 135989 |
| 5 | -236881 |
| 6 | 435876493 |
| 7 | -3174551347 |
| 8 | 790667708347 |
| 9 | -1473406853309 |
| 10 | 11050163107919893 |
| 11 | -20886680047664287 |
| 12 | 9154917271574968829623 |
| 13 | -277315386220087376401 |
| 14 | 803143323197313772705 |