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 | 5 |
| 3 | -119 |
| 4 | -2035 |
| 5 | -239 |
| 6 | 341525 |
| 7 | 3455641 |
| 8 | -23161315 |
| 9 | -815616479 |
| 10 | -4241902555 |
| 11 | 95420159401 |
| 12 | 1671083125805 |
| 13 | 584824319281 |
| 14 | -276564805068235 |
| 15 | -2864483360640839 |
| 16 | 18094618450123325 |
| 17 | 665043872449535041 |
| 18 | 3592448206424508485 |
| 19 | -76467932379726337079 |
| 20 | -1371803070683005304755 |