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 | 32 |
| 2 | 211 |
| 3 | 359 |
| 4 | -538 |
| 5 | 984 |
| 6 | -1866 |
| 7 | 1110 |
| 8 | 32640 |
| 9 | -449760 |
| 10 | 5035200 |
| 11 | -55896960 |
| 12 | 646005600 |
| 13 | -7896549120 |
| 14 | 102604234080 |
| 15 | -1418189492640 |
| 16 | 20828546505600 |
| 17 | -324419255412480 |
| 18 | 5346952977432960 |
| 19 | -93035974518691200 |
| 20 | 1705088403923592960 |
| 21 | -32842738382065931520 |