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 | -3 |
| 3 | -17 |
| 4 | -19 |
| 5 | 126 |
| 6 | 591 |
| 7 | 344 |
| 8 | -5907 |
| 9 | -22373 |
| 10 | 2122 |
| 11 | 280842 |
| 12 | 854063 |
| 13 | -810692 |
| 14 | -13254552 |
| 15 | -31693392 |
| 16 | 67250413 |
| 17 | 615932985 |
| 18 | 1101123015 |
| 19 | -4368359919 |
| 20 | -28043889894 |
| 21 | -33371056204 |
| 22 | 254637122506 |
| 23 | 1245324193704 |
| 24 | 693586015791 |
| 25 | -13913192640499 |