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 | -7 |
| 2 | 9 |
| 3 | -176 |
| 4 | -673 |
| 5 | 1143 |
| 6 | 33201 |
| 7 | 315783 |
| 8 | 2210985 |
| 9 | 1790369 |
| 10 | 44496424 |
| 11 | 1040502519 |
| 12 | -1810005816 |
| 13 | 7445790947 |
| 14 | -134133273672 |
| 15 | -627282760902 |
| 16 | 7903957116411 |
| 17 | -22364317249111 |
| 18 | -200569974966918 |
| 19 | 510174845699733 |
| 20 | 15061484475966460 |
| 21 | 42739249663260682 |
| 22 | 758042190595492047 |