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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 1 |
| 6 | 0 |
| 7 | 0 |
| 8 | 1 |
| 9 | -2 |
| 10 | 0 |
| 11 | 0 |
| 12 | 1 |
| 13 | -9 |
| 14 | 16 |
| 15 | 0 |
| 16 | 0 |
| 17 | 1 |
| 18 | -34 |
| 19 | 477 |
| 20 | -272 |
| 21 | 0 |
| 22 | 0 |
| 23 | 1 |
| 24 | -125 |
| 25 | 11056 |
| 26 | -74601 |
| 27 | 7936 |
| 28 | 0 |
| 29 | 0 |
| 30 | 1 |
| 31 | -461 |
| 32 | 249250 |
| 33 | -14873104 |
| 34 | 25740261 |
| 35 | -353792 |
| 36 | 0 |
| 37 | 0 |
| 38 | 1 |
| 39 | -1715 |
| 40 | 5699149 |
| 41 | -2886735625 |
| 42 | 56814228736 |
| 43 | -16591655817 |
| 44 | 22368256 |
| 45 | 0 |
| 46 | 0 |
| 47 | 1 |
| 48 | -6434 |
| 49 | 132908041 |
| 50 | -574688719793 |
| 51 | 122209131374375 |
| 52 | -495812444583424 |
| 53 | 17929265150637 |
| 54 | -1903757312 |
| 55 | 0 |