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 | 0 |
| 2 | 1 |
| 3 | -6 |
| 4 | 22 |
| 5 | -56 |
| 6 | 121 |
| 7 | -252 |
| 8 | 484 |
| 9 | -798 |
| 10 | 1232 |
| 11 | -2002 |
| 12 | 3145 |
| 13 | -4368 |
| 14 | 5937 |
| 15 | -8630 |
| 16 | 12112 |
| 17 | -15504 |
| 18 | 19678 |
| 19 | -26334 |
| 20 | 34902 |
| 21 | -42762 |
| 22 | 51129 |
| 23 | -65780 |
| 24 | 84337 |
| 25 | -98336 |
| 26 | 114388 |
| 27 | -143304 |
| 28 | 175869 |
| 29 | -201376 |
| 30 | 230120 |
| 31 | -278256 |
| 32 | 336744 |
| 33 | -379000 |
| 34 | 420394 |
| 35 | -502250 |
| 36 | 598459 |
| 37 | -658008 |
| 38 | 723065 |
| 39 | -855042 |
| 40 | 997962 |
| 41 | -1086008 |