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 | -5 |
| 2 | -35 |
| 3 | -185 |
| 4 | -935 |
| 5 | -4685 |
| 6 | -23435 |
| 7 | -117185 |
| 8 | -585935 |
| 9 | -2929685 |
| 10 | -14648435 |
| 11 | -73242185 |
| 12 | -366210935 |
| 13 | -1831054685 |
| 14 | -9155273435 |
| 15 | -45776367185 |
| 16 | -228881835935 |
| 17 | -1144409179685 |
| 18 | -5722045898435 |
| 19 | -28610229492185 |