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 | 5 |
| 2 | 12 |
| 3 | 12 |
| 4 | -29 |
| 5 | -169 |
| 6 | -408 |
| 7 | -408 |
| 8 | 985 |
| 9 | 5741 |
| 10 | 13860 |
| 11 | 13860 |
| 12 | -33461 |
| 13 | -195025 |
| 14 | -470832 |
| 15 | -470832 |
| 16 | 1136689 |
| 17 | 6625109 |
| 18 | 15994428 |
| 19 | 15994428 |
| 20 | -38613965 |
| 21 | -225058681 |
| 22 | -543339720 |
| 23 | -543339720 |
| 24 | 1311738121 |
| 25 | 7645370045 |
| 26 | 18457556052 |
| 27 | 18457556052 |
| 28 | -44560482149 |