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 | -2 |
| 2 | 3 |
| 3 | 4 |
| 4 | -12 |
| 5 | 9 |
| 6 | -8 |
| 7 | 36 |
| 8 | -54 |
| 9 | 27 |
| 10 | 16 |
| 11 | -96 |
| 12 | 216 |
| 13 | -216 |
| 14 | 81 |
| 15 | -32 |
| 16 | 240 |
| 17 | -720 |
| 18 | 1080 |
| 19 | -810 |
| 20 | 243 |
| 21 | 64 |
| 22 | -576 |
| 23 | 2160 |
| 24 | -4320 |
| 25 | 4860 |
| 26 | -2916 |
| 27 | 729 |
| 28 | -128 |
| 29 | 1344 |
| 30 | -6048 |
| 31 | 15120 |
| 32 | -22680 |
| 33 | 20412 |
| 34 | -10206 |
| 35 | 2187 |
| 36 | 256 |
| 37 | -3072 |
| 38 | 16128 |
| 39 | -48384 |
| 40 | 90720 |
| 41 | -108864 |
| 42 | 81648 |
| 43 | -34992 |
| 44 | 6561 |
| 45 | -512 |
| 46 | 6912 |
| 47 | -41472 |
| 48 | 145152 |
| 49 | -326592 |
| 50 | 489888 |
| 51 | -489888 |
| 52 | 314928 |
| 53 | -118098 |
| 54 | 19683 |