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 | 4 |
| 2 | -6 |
| 3 | 6 |
| 4 | -21 |
| 5 | 35 |
| 6 | -35 |
| 7 | 21 |
| 8 | -10 |
| 9 | 221 |
| 10 | -77 |
| 11 | 55 |
| 12 | -55 |
| 13 | 77 |
| 14 | -221 |
| 15 | 10 |
| 16 | -33 |
| 17 | 46513 |
| 18 | -493 |
| 19 | 377 |
| 20 | -119 |
| 21 | 187 |
| 22 | -1333 |
| 23 | 559 |
| 24 | -559 |
| 25 | 1333 |
| 26 | -187 |
| 27 | 119 |
| 28 | -377 |
| 29 | 493 |
| 30 | -46513 |
| 31 | 33 |
| 32 | -14 |
| 33 | 143 |
| 34 | -209 |
| 35 | 629 |
| 36 | -14527 |
| 37 | 2881 |
| 38 | -1189 |
| 39 | 533 |
| 40 | -161 |
| 41 | 391 |
| 42 | -15229 |
| 43 | 2449 |
| 44 | -2263 |
| 45 | 3139 |
| 46 | -1073 |
| 47 | 95 |
| 48 | -95 |