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 | 0 |
| 3 | 8 |
| 4 | -32 |
| 5 | -128 |
| 6 | 320 |
| 7 | 128 |
| 8 | 2048 |
| 9 | 8192 |
| 10 | -15360 |
| 11 | 2048 |
| 12 | -131072 |
| 13 | -524288 |
| 14 | 1064960 |
| 15 | 32768 |
| 16 | 8388608 |
| 17 | 33554432 |
| 18 | -66846720 |
| 19 | 524288 |
| 20 | -536870912 |
| 21 | -2147483648 |
| 22 | 4299161600 |
| 23 | 8388608 |
| 24 | 34359738368 |
| 25 | 137438953472 |
| 26 | -274810798080 |
| 27 | 134217728 |