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 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | -1 |
| 5 | 0 |
| 6 | 2 |
| 7 | -4 |
| 8 | 3 |
| 9 | 5 |
| 10 | -20 |
| 11 | 29 |
| 12 | -1 |
| 13 | -94 |
| 14 | 221 |
| 15 | -191 |
| 16 | -327 |
| 17 | 1454 |
| 18 | -2282 |
| 19 | 162 |
| 20 | 8002 |
| 21 | -19902 |
| 22 | 18275 |
| 23 | 30505 |
| 24 | -143511 |
| 25 | 234364 |
| 26 | -24437 |
| 27 | -841723 |
| 28 | 2164873 |
| 29 | -2069014 |
| 30 | -3325410 |
| 31 | 16315410 |
| 32 | -27375369 |
| 33 | 3714435 |
| 34 | 98829168 |
| 35 | -260605269 |
| 36 | 257026289 |
| 37 | 395719442 |
| 38 | -2013114895 |
| 39 | 3450787313 |
| 40 | -572442080 |
| 41 | -12414009687 |
| 42 | 33423611731 |
| 43 | -33865948418 |
| 44 | -49805740764 |
| 45 | 262037063892 |