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 | -3 |
| 2 | -3 |
| 3 | 7 |
| 4 | 7 |
| 5 | -9 |
| 6 | -9 |
| 7 | 47 |
| 8 | 47 |
| 9 | -123 |
| 10 | -123 |
| 11 | 161 |
| 12 | 161 |
| 13 | -843 |
| 14 | -843 |
| 15 | 2207 |
| 16 | 2207 |
| 17 | -2889 |
| 18 | -2889 |
| 19 | 15127 |
| 20 | 15127 |
| 21 | -39603 |
| 22 | -39603 |
| 23 | 51841 |
| 24 | 51841 |
| 25 | -271443 |
| 26 | -271443 |
| 27 | 710647 |
| 28 | 710647 |
| 29 | -930249 |
| 30 | -930249 |
| 31 | 4870847 |
| 32 | 4870847 |
| 33 | -12752043 |
| 34 | -12752043 |