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 | 0 |
| 3 | -16 |
| 4 | -256 |
| 5 | -4096 |
| 6 | 0 |
| 7 | 16777216 |
| 8 | 4294967296 |
| 9 | 1099511627776 |
| 10 | 0 |
| 11 | -1152921504606846976 |
| 12 | -4722366482869645213696 |
| 13 | -19342813113834066795298816 |
| 14 | 0 |
| 15 | 5192296858534827628530496329220096 |
| 16 | 340282366920938463463374607431768211456 |