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 | -4 |
| 2 | 1 |
| 3 | 3 |
| 4 | -6 |
| 5 | 1 |
| 6 | -12 |
| 7 | 9 |
| 8 | -9 |
| 9 | 1 |
| 10 | -117 |
| 11 | -26 |
| 12 | 26 |
| 13 | -13 |
| 14 | 1 |
| 15 | -1656 |
| 16 | -216 |
| 17 | -69 |
| 18 | 63 |
| 19 | -18 |
| 20 | 1 |
| 21 | -28506 |
| 22 | -3396 |
| 23 | -294 |
| 24 | -212 |
| 25 | 132 |
| 26 | -24 |
| 27 | 1 |
| 28 | -578274 |
| 29 | -63116 |
| 30 | -5766 |
| 31 | -124 |
| 32 | -620 |
| 33 | 248 |
| 34 | -31 |
| 35 | 1 |
| 36 | -13504179 |
| 37 | -1365546 |
| 38 | -116116 |
| 39 | -8892 |
| 40 | 1170 |
| 41 | -1612 |
| 42 | 429 |
| 43 | -39 |
| 44 | 1 |
| 45 | -356633784 |
| 46 | -33696726 |
| 47 | -2696316 |
| 48 | -186860 |
| 49 | -15000 |
| 50 | 6228 |
| 51 | -3736 |