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 | 4 |
| 3 | -2 |
| 4 | 12 |
| 5 | -8 |
| 6 | 9 |
| 7 | 32 |
| 8 | -16 |
| 9 | 120 |
| 10 | -60 |
| 11 | 80 |
| 12 | 0 |
| 13 | 952 |
| 14 | -768 |
| 15 | 525 |
| 16 | 192 |
| 17 | 160 |
| 18 | 5664 |
| 19 | -5008 |
| 20 | 12396 |
| 21 | -5670 |
| 22 | 448 |
| 23 | 896 |
| 24 | 27888 |
| 25 | -20672 |
| 26 | 162740 |
| 27 | -133128 |
| 28 | 72765 |
| 29 | 1024 |
| 30 | 3584 |
| 31 | 120064 |
| 32 | -46720 |
| 33 | 1537216 |
| 34 | -1562464 |
| 35 | 2557296 |
| 36 | -1081080 |
| 37 | 2304 |
| 38 | 12288 |
| 39 | 467712 |
| 40 | 76800 |