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 | 1 |
| 2 | 0 |
| 3 | -1 |
| 4 | -2 |
| 5 | 0 |
| 6 | 4 |
| 7 | 5 |
| 8 | 0 |
| 9 | -10 |
| 10 | -12 |
| 11 | 0 |
| 12 | 20 |
| 13 | 26 |
| 14 | 0 |
| 15 | -39 |
| 16 | -50 |
| 17 | 0 |
| 18 | 76 |
| 19 | 92 |
| 20 | 0 |
| 21 | -140 |
| 22 | -168 |
| 23 | 0 |
| 24 | 244 |
| 25 | 295 |
| 26 | 0 |
| 27 | -415 |
| 28 | -496 |
| 29 | 0 |
| 30 | 696 |
| 31 | 818 |
| 32 | 0 |
| 33 | -1140 |
| 34 | -1332 |
| 35 | 0 |
| 36 | 1820 |
| 37 | 2126 |
| 38 | 0 |
| 39 | -2861 |
| 40 | -3324 |
| 41 | 0 |
| 42 | 4448 |
| 43 | 5126 |
| 44 | 0 |
| 45 | -6816 |
| 46 | -7824 |
| 47 | 0 |
| 48 | 10292 |
| 49 | 11793 |
| 50 | 0 |
| 51 | -15372 |
| 52 | -17548 |
| 53 | 0 |
| 54 | 22756 |