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 | -1 |
| 3 | 4 |
| 4 | -27 |
| 5 | 256 |
| 6 | -3125 |
| 7 | 46656 |
| 8 | -823543 |
| 9 | 16777216 |
| 10 | -387420489 |
| 11 | 10000000000 |
| 12 | -285311670611 |
| 13 | 8916100448256 |
| 14 | -302875106592253 |
| 15 | 11112006825558016 |
| 16 | -437893890380859375 |
| 17 | 18446744073709551616 |
| 18 | -827240261886336764177 |