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 | 0 |
| 5 | 2 |
| 6 | -3 |
| 7 | 4 |
| 8 | -4 |
| 9 | 4 |
| 10 | -9 |
| 11 | 14 |
| 12 | -19 |
| 13 | 30 |
| 14 | -42 |
| 15 | 50 |
| 16 | -76 |
| 17 | 128 |
| 18 | -194 |
| 19 | 286 |
| 20 | -412 |
| 21 | 598 |
| 22 | -909 |
| 23 | 1386 |
| 24 | -2100 |
| 25 | 3178 |
| 26 | -4763 |
| 27 | 7122 |
| 28 | -10758 |
| 29 | 16414 |
| 30 | -25061 |
| 31 | 38056 |
| 32 | -57643 |
| 33 | 87568 |
| 34 | -133436 |
| 35 | 203618 |
| 36 | -311128 |
| 37 | 475536 |
| 38 | -726355 |
| 39 | 1109718 |
| 40 | -1697766 |
| 41 | 2601166 |
| 42 | -3987903 |
| 43 | 6114666 |