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 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | -3 |
| 5 | 1 |
| 6 | 0 |
| 7 | 6 |
| 8 | -8 |
| 9 | 1 |
| 10 | 0 |
| 11 | -10 |
| 12 | 40 |
| 13 | -15 |
| 14 | 1 |
| 15 | 0 |
| 16 | 15 |
| 17 | -160 |
| 18 | 135 |
| 19 | -24 |
| 20 | 1 |
| 21 | 0 |
| 22 | -21 |
| 23 | 560 |
| 24 | -945 |
| 25 | 336 |
| 26 | -35 |
| 27 | 1 |
| 28 | 0 |
| 29 | 28 |
| 30 | -1792 |
| 31 | 5670 |
| 32 | -3584 |
| 33 | 700 |
| 34 | -48 |
| 35 | 1 |
| 36 | 0 |
| 37 | -36 |
| 38 | 5376 |
| 39 | -30618 |
| 40 | 32256 |
| 41 | -10500 |
| 42 | 1296 |
| 43 | -63 |
| 44 | 1 |
| 45 | 0 |
| 46 | 45 |
| 47 | -15360 |
| 48 | 153090 |
| 49 | -258048 |
| 50 | 131250 |
| 51 | -25920 |
| 52 | 2205 |
| 53 | -80 |
| 54 | 1 |
| 55 | 0 |
| 56 | -55 |
| 57 | 42240 |
| 58 | -721710 |
| 59 | 1892352 |
| 60 | -1443750 |
| 61 | 427680 |
| 62 | -56595 |
| 63 | 3520 |
| 64 | -99 |
| 65 | 1 |