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 | -11 |
| 3 | 36 |
| 4 | -36 |
| 5 | 36 |
| 6 | -3786 |
| 7 | 63786 |
| 8 | -405036 |
| 9 | 1215036 |
| 10 | -4368786 |
| 11 | 45022536 |
| 12 | -380988786 |
| 13 | 2242736286 |
| 14 | -7681046286 |
| 15 | 26949825036 |
| 16 | -435049072536 |
| 17 | 4543990507536 |
| 18 | -25626723348786 |
| 19 | 80068989783786 |
| 20 | -100028016375036 |
| 21 | 1579550678122536 |
| 22 | -31186023693776286 |
| 23 | 252408733196148786 |