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 | -11 |
| 3 | -23 |
| 4 | 109 |
| 5 | 385 |
| 6 | -923 |
| 7 | -5543 |
| 8 | 5533 |
| 9 | 72049 |
| 10 | 5653 |
| 11 | -858935 |
| 12 | -926771 |
| 13 | 9380449 |
| 14 | 20501701 |
| 15 | -92063687 |
| 16 | -338084099 |
| 17 | 766680145 |
| 18 | 4823689333 |
| 19 | -4376472407 |
| 20 | -62260744403 |
| 21 | -9743075519 |
| 22 | 737385857317 |
| 23 | 854302763545 |
| 24 | -7994327524259 |