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 | 0 |
| 4 | -1 |
| 5 | 2 |
| 6 | -4 |
| 7 | 7 |
| 8 | -11 |
| 9 | 16 |
| 10 | -21 |
| 11 | 26 |
| 12 | -30 |
| 13 | 33 |
| 14 | -33 |
| 15 | 28 |
| 16 | -14 |
| 17 | -13 |
| 18 | 59 |
| 19 | -131 |
| 20 | 238 |
| 21 | -390 |
| 22 | 598 |
| 23 | -873 |
| 24 | 1225 |
| 25 | -1663 |
| 26 | 2194 |
| 27 | -2822 |
| 28 | 3544 |
| 29 | -4347 |
| 30 | 5202 |
| 31 | -6059 |
| 32 | 6838 |
| 33 | -7420 |
| 34 | 7633 |
| 35 | -7238 |
| 36 | 5911 |
| 37 | -3226 |
| 38 | -1365 |
| 39 | 8552 |
| 40 | -19190 |
| 41 | 34320 |
| 42 | -55189 |
| 43 | 83266 |
| 44 | -120254 |
| 45 | 168094 |
| 46 | -228958 |