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 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | -5 |
| 7 | 15 |
| 8 | -34 |
| 9 | 63 |
| 10 | -97 |
| 11 | 115 |
| 12 | -54 |
| 13 | -251 |
| 14 | 1184 |
| 15 | -3536 |
| 16 | 8736 |
| 17 | -18993 |
| 18 | 37009 |
| 19 | -64545 |
| 20 | 98442 |
| 21 | -121393 |
| 22 | 82008 |
| 23 | 147432 |
| 24 | -860818 |
| 25 | 2710023 |
| 26 | -7110594 |
| 27 | 17077281 |
| 28 | -38873146 |
| 29 | 85085287 |
| 30 | -179965647 |
| 31 | 367885014 |
| 32 | -725051280 |
| 33 | 1372311999 |
| 34 | -2481473550 |
| 35 | 4257624252 |