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) |
|---|---|
| 21 | 1 |
| 22 | -21 |
| 23 | 210 |
| 24 | -1330 |
| 25 | 5964 |
| 26 | -19929 |
| 27 | 50253 |
| 28 | -91920 |
| 29 | 97965 |
| 30 | 51604 |
| 31 | -526659 |
| 32 | 1389297 |
| 33 | -2280320 |
| 34 | 2118690 |
| 35 | 769065 |
| 36 | -7613319 |
| 37 | 17220042 |
| 38 | -23999430 |
| 39 | 18024405 |
| 40 | 10748850 |
| 41 | -63778953 |
| 42 | 124134772 |
| 43 | -152793270 |
| 44 | 99072120 |
| 45 | 71722224 |
| 46 | -341062407 |
| 47 | 610085721 |