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 | -3 |
| 2 | 1 |
| 3 | 6 |
| 4 | -6 |
| 5 | 1 |
| 6 | -10 |
| 7 | 21 |
| 8 | -9 |
| 9 | 1 |
| 10 | 15 |
| 11 | -56 |
| 12 | 45 |
| 13 | -12 |
| 14 | 1 |
| 15 | -21 |
| 16 | 126 |
| 17 | -165 |
| 18 | 78 |
| 19 | -15 |
| 20 | 1 |
| 21 | 28 |
| 22 | -252 |
| 23 | 495 |
| 24 | -364 |
| 25 | 120 |
| 26 | -18 |
| 27 | 1 |
| 28 | -36 |
| 29 | 462 |
| 30 | -1287 |
| 31 | 1365 |
| 32 | -680 |
| 33 | 171 |
| 34 | -21 |
| 35 | 1 |
| 36 | 45 |
| 37 | -792 |
| 38 | 3003 |
| 39 | -4368 |
| 40 | 3060 |
| 41 | -1140 |
| 42 | 231 |
| 43 | -24 |
| 44 | 1 |
| 45 | -55 |
| 46 | 1287 |
| 47 | -6435 |
| 48 | 12376 |
| 49 | -11628 |
| 50 | 5985 |
| 51 | -1771 |
| 52 | 300 |
| 53 | -27 |
| 54 | 1 |