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 | -4 |
| 2 | 26 |
| 3 | -49 |
| 4 | 246 |
| 5 | -619 |
| 6 | 2621 |
| 7 | -7774 |
| 8 | 30126 |
| 9 | -97879 |
| 10 | 363131 |
| 11 | -1237504 |
| 12 | 4497801 |
| 13 | -15702574 |
| 14 | 56538746 |
| 15 | -199764994 |
| 16 | 716265246 |
| 17 | -2545683874 |
| 18 | 9110943101 |
| 19 | -32474838004 |
| 20 | 116135818131 |
| 21 | -414537600379 |
| 22 | 1481979727826 |
| 23 | -5293483738474 |
| 24 | 18921861083121 |
| 25 | -67610126265619 |
| 26 | 241664630238746 |