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 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | -1 |
| 5 | 6 |
| 6 | 4 |
| 7 | 8 |
| 8 | -25 |
| 9 | 37 |
| 10 | 16 |
| 11 | 12 |
| 12 | -106 |
| 13 | 14 |
| 14 | 92 |
| 15 | 384 |
| 16 | -561 |
| 17 | 18 |
| 18 | -65 |
| 19 | 20 |
| 20 | -706 |
| 21 | 2552 |
| 22 | 1948 |
| 23 | 24 |
| 24 | -15658 |
| 25 | 3151 |
| 26 | 8048 |
| 27 | 20440 |
| 28 | -2570 |
| 29 | 30 |
| 30 | -33326 |
| 31 | 32 |
| 32 | -135393 |
| 33 | 178512 |
| 34 | 130816 |
| 35 | 94968 |
| 36 | -583219 |
| 37 | 38 |
| 38 | 523964 |
| 39 | 1596560 |
| 40 | -2465370 |
| 41 | 42 |
| 42 | -2521186 |
| 43 | 44 |
| 44 | -15082 |
| 45 | 16364502 |
| 46 | 8388124 |
| 47 | 48 |
| 48 | -78560082 |
| 49 | 823593 |
| 50 | 23888231 |