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 | 1 |
| 2 | -2 |
| 3 | -8 |
| 4 | 10 |
| 5 | 106 |
| 6 | -44 |
| 7 | -1952 |
| 8 | -1028 |
| 9 | 45820 |
| 10 | 73576 |
| 11 | -1301024 |
| 12 | -3729032 |
| 13 | 43107832 |
| 14 | 188540080 |
| 15 | -1621988864 |
| 16 | -10106292464 |
| 17 | 67749173008 |
| 18 | 583170088672 |
| 19 | -3075285253760 |
| 20 | -36315980308064 |
| 21 | 148201134917536 |
| 22 | 2436107894325568 |
| 23 | -7345167010231808 |