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 | -3 |
| 2 | 9 |
| 3 | -22 |
| 4 | 48 |
| 5 | -99 |
| 6 | 194 |
| 7 | -363 |
| 8 | 657 |
| 9 | -1155 |
| 10 | 1977 |
| 11 | -3312 |
| 12 | 5443 |
| 13 | -8787 |
| 14 | 13968 |
| 15 | -21894 |
| 16 | 33873 |
| 17 | -51795 |
| 18 | 78345 |
| 19 | -117312 |
| 20 | 174033 |
| 21 | -255945 |
| 22 | 373353 |
| 23 | -540486 |
| 24 | 776848 |
| 25 | -1109040 |
| 26 | 1573209 |
| 27 | -2218198 |
| 28 | 3109713 |
| 29 | -4335840 |
| 30 | 6014123 |
| 31 | -8300811 |
| 32 | 11402928 |