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 | 3 |
| 2 | 2 |
| 3 | 8 |
| 4 | -9 |
| 5 | 62 |
| 6 | -230 |
| 7 | 1054 |
| 8 | -4753 |
| 9 | 22208 |
| 10 | -105419 |
| 11 | 508396 |
| 12 | -2482284 |
| 13 | 12248430 |
| 14 | -60980860 |
| 15 | 305955372 |
| 16 | -1545397447 |
| 17 | 7852100312 |
| 18 | -40105277621 |
| 19 | 205798130624 |
| 20 | -1060467961487 |
| 21 | 5485199090834 |
| 22 | -28469067353663 |
| 23 | 148220323891484 |
| 24 | -773892318396664 |
| 25 | 4051261817405034 |