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 | 2 |
| 2 | 1 |
| 3 | -4 |
| 4 | -9 |
| 5 | 2 |
| 6 | 43 |
| 7 | 72 |
| 8 | -53 |
| 9 | -418 |
| 10 | -549 |
| 11 | 860 |
| 12 | 4161 |
| 13 | 4006 |
| 14 | -11619 |
| 15 | -41104 |
| 16 | -24989 |
| 17 | 145046 |
| 18 | 399571 |
| 19 | 89796 |
| 20 | -1723259 |
| 21 | -3787914 |
| 22 | 829841 |
| 23 | 19739016 |
| 24 | 34642741 |
| 25 | -26909998 |
| 26 | -219300587 |
| 27 | -300591148 |
| 28 | 467328447 |
| 29 | 2369124842 |