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 | -2 |
| 4 | -3 |
| 5 | 14 |
| 6 | -29 |
| 7 | 38 |
| 8 | -19 |
| 9 | -58 |
| 10 | 211 |
| 11 | -402 |
| 12 | 477 |
| 13 | -130 |
| 14 | -1021 |
| 15 | 3126 |
| 16 | -5491 |
| 17 | 5814 |
| 18 | 115 |
| 19 | -17026 |
| 20 | 45565 |
| 21 | -73874 |
| 22 | 68131 |
| 23 | 28742 |
| 24 | -273363 |
| 25 | 654246 |
| 26 | -977645 |
| 27 | 754318 |
| 28 | 777501 |
| 29 | -4264610 |
| 30 | 9260355 |
| 31 | -12701098 |
| 32 | 7612621 |
| 33 | 15996566 |
| 34 | -65007949 |
| 35 | 129244574 |
| 36 | -161488067 |
| 37 | 63715662 |
| 38 | 292545891 |