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 | 1 |
| 3 | -1 |
| 4 | -1 |
| 5 | -1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 11 |
| 9 | -1 |
| 10 | -1 |
| 11 | 0 |
| 12 | -3 |
| 13 | -9 |
| 14 | 5 |
| 15 | 1 |
| 16 | 0 |
| 17 | 3 |
| 18 | 81 |
| 19 | 7 |
| 20 | -73 |
| 21 | -1 |
| 22 | 0 |
| 23 | 3 |
| 24 | 73 |
| 25 | -1261 |
| 26 | -1183 |
| 27 | 53 |
| 28 | 1 |
| 29 | 0 |
| 30 | -3 |
| 31 | -1231 |
| 32 | 5251 |
| 33 | 8989 |
| 34 | 1451 |
| 35 | -731 |
| 36 | -1 |
| 37 | 0 |
| 38 | 0 |
| 39 | 7 |
| 40 | 397 |
| 41 | -12491 |
| 42 | -19877 |
| 43 | -15047 |
| 44 | 1567 |
| 45 | 1 |
| 46 | 0 |
| 47 | 0 |
| 48 | 0 |
| 49 | -7 |
| 50 | -1483 |
| 51 | 50111 |
| 52 | 69761 |
| 53 | 45959 |
| 54 | -5261 |
| 55 | -1 |