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 | 20 |
| 2 | -62 |
| 3 | 216 |
| 4 | -641 |
| 5 | 1636 |
| 6 | -3778 |
| 7 | 8248 |
| 8 | -17277 |
| 9 | 34664 |
| 10 | -66878 |
| 11 | 125312 |
| 12 | -229252 |
| 13 | 409676 |
| 14 | -716420 |
| 15 | 1230328 |
| 16 | -2079227 |
| 17 | 3460416 |
| 18 | -5677816 |
| 19 | 9198424 |
| 20 | -14729608 |
| 21 | 23328520 |
| 22 | -36567242 |
| 23 | 56774712 |
| 24 | -87369461 |
| 25 | 133321908 |
| 26 | -201825396 |
| 27 | 303248408 |
| 28 | -452431503 |