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 | 2 |
| 2 | 8 |
| 3 | 32 |
| 4 | 128 |
| 5 | 502 |
| 6 | 1904 |
| 7 | 6862 |
| 8 | 22784 |
| 9 | 64832 |
| 10 | 120008 |
| 11 | -223606 |
| 12 | -4311424 |
| 13 | -33271366 |
| 14 | -205802344 |
| 15 | -1142307968 |
| 16 | -5919738880 |
| 17 | -29159028386 |
| 18 | -137718099760 |
| 19 | -626077804826 |
| 20 | -2740865583872 |
| 21 | -11523690799904 |
| 22 | -46214332516520 |
| 23 | -174358991625134 |
| 24 | -601230820510720 |