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 | -1 |
| 3 | -1 |
| 4 | 0 |
| 5 | 1 |
| 6 | 0 |
| 7 | 3 |
| 8 | 2 |
| 9 | 3 |
| 10 | 1 |
| 11 | 3 |
| 12 | -2 |
| 13 | 0 |
| 14 | -6 |
| 15 | -8 |
| 16 | -12 |
| 17 | -14 |
| 18 | -18 |
| 19 | -19 |
| 20 | -19 |
| 21 | -15 |
| 22 | -3 |
| 23 | 4 |
| 24 | 29 |
| 25 | 46 |
| 26 | 90 |
| 27 | 114 |
| 28 | 165 |
| 29 | 192 |
| 30 | 248 |
| 31 | 252 |
| 32 | 276 |
| 33 | 232 |
| 34 | 185 |
| 35 | 29 |
| 36 | -143 |
| 37 | -454 |
| 38 | -811 |
| 39 | -1324 |
| 40 | -1909 |
| 41 | -2609 |
| 42 | -3348 |
| 43 | -4132 |
| 44 | -4851 |
| 45 | -5386 |
| 46 | -5653 |
| 47 | -5380 |
| 48 | -4470 |
| 49 | -2477 |
| 50 | 664 |
| 51 | 5582 |
| 52 | 12193 |
| 53 | 21314 |