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 | 5 |
| 3 | -4 |
| 4 | 25 |
| 5 | -30 |
| 6 | 6 |
| 7 | 125 |
| 8 | -200 |
| 9 | 40 |
| 10 | 40 |
| 11 | -4 |
| 12 | 625 |
| 13 | -1250 |
| 14 | 250 |
| 15 | 500 |
| 16 | -25 |
| 17 | -100 |
| 18 | 1 |
| 19 | 3125 |
| 20 | -7500 |
| 21 | 1500 |
| 22 | 4500 |
| 23 | -150 |
| 24 | -1200 |
| 25 | 6 |
| 26 | -400 |
| 27 | 60 |
| 28 | 60 |
| 29 | 15625 |
| 30 | -43750 |
| 31 | 8750 |
| 32 | 35000 |
| 33 | -875 |
| 34 | -10500 |
| 35 | 35 |
| 36 | -7000 |
| 37 | 700 |
| 38 | 700 |
| 39 | 1400 |
| 40 | -14 |
| 41 | -70 |