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 | 0 |
| 2 | 0 |
| 3 | -3 |
| 4 | 0 |
| 5 | 0 |
| 6 | 3 |
| 7 | -7 |
| 8 | 0 |
| 9 | -1 |
| 10 | 21 |
| 11 | -11 |
| 12 | 0 |
| 13 | -21 |
| 14 | 54 |
| 15 | -15 |
| 16 | 7 |
| 17 | -96 |
| 18 | 122 |
| 19 | -19 |
| 20 | 74 |
| 21 | -311 |
| 22 | 217 |
| 23 | -44 |
| 24 | 351 |
| 25 | -768 |
| 26 | 367 |
| 27 | -209 |
| 28 | 1227 |
| 29 | -1663 |
| 30 | 591 |
| 31 | -989 |
| 32 | 3402 |
| 33 | -3225 |
| 34 | 1156 |
| 35 | -3609 |
| 36 | 8289 |
| 37 | -5815 |
| 38 | 3053 |
| 39 | -11096 |
| 40 | 18015 |
| 41 | -10176 |
| 42 | 9466 |
| 43 | -29593 |
| 44 | 36249 |
| 45 | -18454 |
| 46 | 28960 |
| 47 | -71093 |
| 48 | 68438 |