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 | 1 |
| 2 | -3 |
| 3 | -3 |
| 4 | 7 |
| 5 | 7 |
| 6 | -13 |
| 7 | -13 |
| 8 | 22 |
| 9 | 22 |
| 10 | -34 |
| 11 | -34 |
| 12 | 50 |
| 13 | 50 |
| 14 | -70 |
| 15 | -70 |
| 16 | 95 |
| 17 | 95 |
| 18 | -125 |
| 19 | -125 |
| 20 | 161 |
| 21 | 161 |
| 22 | -203 |
| 23 | -203 |
| 24 | 252 |
| 25 | 252 |
| 26 | -308 |
| 27 | -308 |
| 28 | 372 |
| 29 | 372 |
| 30 | -444 |
| 31 | -444 |
| 32 | 525 |
| 33 | 525 |
| 34 | -615 |
| 35 | -615 |
| 36 | 715 |
| 37 | 715 |
| 38 | -825 |
| 39 | -825 |
| 40 | 946 |
| 41 | 946 |
| 42 | -1078 |
| 43 | -1078 |
| 44 | 1222 |
| 45 | 1222 |
| 46 | -1378 |
| 47 | -1378 |
| 48 | 1547 |
| 49 | 1547 |
| 50 | -1729 |
| 51 | -1729 |
| 52 | 1925 |
| 53 | 1925 |
| 54 | -2135 |
| 55 | -2135 |