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 | 1 |
| 3 | 3 |
| 4 | 1 |
| 5 | -23 |
| 6 | -2 |
| 7 | -28 |
| 8 | -2435 |
| 9 | 253 |
| 10 | 118966 |
| 11 | 158400 |
| 12 | -5277106 |
| 13 | -6453094 |
| 14 | 377003877 |
| 15 | 150562341 |
| 16 | -38919169331 |
| 17 | -49489639843 |
| 18 | 4097920244054 |
| 19 | 15989402021656 |
| 20 | -397866849121614 |
| 21 | -3949517739363706 |
| 22 | 34992745696351023 |
| 23 | 937723673130987379 |
| 24 | -2417716098650478930 |
| 25 | -223227071403982903362 |