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 | 0 |
| 3 | -4 |
| 4 | 9 |
| 5 | -18 |
| 6 | 60 |
| 7 | -40 |
| 8 | 33 |
| 9 | 4 |
| 10 | 90 |
| 11 | -108 |
| 12 | 240 |
| 13 | -154 |
| 14 | 120 |
| 15 | 48 |
| 16 | 93 |
| 17 | -270 |
| 18 | 288 |
| 19 | -340 |
| 20 | 468 |
| 21 | 0 |
| 22 | 180 |
| 23 | -504 |
| 24 | 672 |
| 25 | -54 |
| 26 | 210 |
| 27 | 52 |
| 28 | 768 |
| 29 | -810 |
| 30 | 3096 |
| 31 | -928 |
| 32 | 237 |
| 33 | -192 |
| 34 | 270 |
| 35 | -480 |
| 36 | 948 |
| 37 | -1330 |
| 38 | 300 |
| 39 | -336 |
| 40 | 1404 |
| 41 | -1638 |
| 42 | 5088 |
| 43 | -1804 |
| 44 | 1584 |
| 45 | 648 |
| 46 | 360 |
| 47 | -2160 |
| 48 | 1680 |
| 49 | -216 |
| 50 | 684 |
| 51 | -720 |
| 52 | 2100 |
| 53 | -2754 |
| 54 | 1116 |
| 55 | -1584 |
| 56 | 2400 |
| 57 | -960 |
| 58 | 450 |
| 59 | -3420 |
| 60 | 10080 |