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 | -2 |
| 2 | 3 |
| 3 | -4 |
| 4 | 7 |
| 5 | -12 |
| 6 | 17 |
| 7 | -24 |
| 8 | 36 |
| 9 | -52 |
| 10 | 71 |
| 11 | -96 |
| 12 | 133 |
| 13 | -182 |
| 14 | 240 |
| 15 | -316 |
| 16 | 420 |
| 17 | -552 |
| 18 | 713 |
| 19 | -916 |
| 20 | 1182 |
| 21 | -1516 |
| 22 | 1920 |
| 23 | -2424 |
| 24 | 3063 |
| 25 | -3852 |
| 26 | 4806 |
| 27 | -5976 |
| 28 | 7430 |
| 29 | -9204 |
| 30 | 11336 |
| 31 | -13924 |
| 32 | 17088 |
| 33 | -20908 |
| 34 | 25473 |
| 35 | -30960 |
| 36 | 37586 |
| 37 | -45518 |
| 38 | 54939 |
| 39 | -66172 |
| 40 | 79603 |
| 41 | -95556 |
| 42 | 114399 |