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 | 1 |
| 2 | -1 |
| 3 | 0 |
| 4 | -1 |
| 5 | -1 |
| 6 | 2 |
| 7 | -4 |
| 8 | 4 |
| 9 | -7 |
| 10 | 8 |
| 11 | -10 |
| 12 | 9 |
| 13 | -5 |
| 14 | -6 |
| 15 | 19 |
| 16 | -40 |
| 17 | 70 |
| 18 | -110 |
| 19 | 138 |
| 20 | -158 |
| 21 | 154 |
| 22 | -93 |
| 23 | -70 |
| 24 | 355 |
| 25 | -797 |
| 26 | 1408 |
| 27 | -2160 |
| 28 | 2925 |
| 29 | -3479 |
| 30 | 3399 |
| 31 | -2080 |
| 32 | -1299 |
| 33 | 7593 |
| 34 | -17673 |
| 35 | 32014 |
| 36 | -49928 |
| 37 | 68683 |
| 38 | -82847 |
| 39 | 82807 |
| 40 | -53620 |
| 41 | -24942 |
| 42 | 176293 |
| 43 | -422887 |
| 44 | 777264 |
| 45 | -1226688 |
| 46 | 1710686 |
| 47 | -2093347 |