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 | 1 |
| 4 | 4 |
| 5 | -12 |
| 6 | 13 |
| 7 | -6 |
| 8 | 1 |
| 9 | 8 |
| 10 | -36 |
| 11 | 66 |
| 12 | -63 |
| 13 | 33 |
| 14 | -9 |
| 15 | 1 |
| 16 | 16 |
| 17 | -96 |
| 18 | 248 |
| 19 | -360 |
| 20 | 321 |
| 21 | -180 |
| 22 | 62 |
| 23 | -12 |
| 24 | 1 |
| 25 | 32 |
| 26 | -240 |
| 27 | 800 |
| 28 | -1560 |
| 29 | 1970 |
| 30 | -1683 |
| 31 | 985 |
| 32 | -390 |
| 33 | 100 |
| 34 | -15 |
| 35 | 1 |
| 36 | 64 |
| 37 | -576 |
| 38 | 2352 |
| 39 | -5760 |
| 40 | 9420 |
| 41 | -10836 |
| 42 | 8989 |
| 43 | -5418 |
| 44 | 2355 |
| 45 | -720 |
| 46 | 147 |
| 47 | -18 |
| 48 | 1 |
| 49 | 128 |
| 50 | -1344 |
| 51 | 6496 |
| 52 | -19152 |
| 53 | 38472 |
| 54 | -55692 |
| 55 | 59906 |
| 56 | -48639 |
| 57 | 29953 |
| 58 | -13923 |
| 59 | 4809 |
| 60 | -1197 |
| 61 | 203 |
| 62 | -21 |
| 63 | 1 |