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 | 2 |
| 1 | 2 |
| 2 | 2 |
| 3 | -7 |
| 4 | 11 |
| 5 | -16 |
| 6 | 29 |
| 7 | -61 |
| 8 | 128 |
| 9 | -259 |
| 10 | 515 |
| 11 | -1024 |
| 12 | 2045 |
| 13 | -4093 |
| 14 | 8192 |
| 15 | -16387 |
| 16 | 32771 |
| 17 | -65536 |
| 18 | 131069 |
| 19 | -262141 |
| 20 | 524288 |
| 21 | -1048579 |
| 22 | 2097155 |
| 23 | -4194304 |
| 24 | 8388605 |
| 25 | -16777213 |
| 26 | 33554432 |
| 27 | -67108867 |
| 28 | 134217731 |
| 29 | -268435456 |
| 30 | 536870909 |
| 31 | -1073741821 |
| 32 | 2147483648 |