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 | 4 |
| 3 | -8 |
| 4 | 16 |
| 5 | -28 |
| 6 | 48 |
| 7 | -80 |
| 8 | 128 |
| 9 | -202 |
| 10 | 312 |
| 11 | -472 |
| 12 | 704 |
| 13 | -1036 |
| 14 | 1504 |
| 15 | -2160 |
| 16 | 3072 |
| 17 | -4324 |
| 18 | 6036 |
| 19 | -8360 |
| 20 | 11488 |
| 21 | -15680 |
| 22 | 21264 |
| 23 | -28656 |
| 24 | 38400 |
| 25 | -51182 |
| 26 | 67864 |
| 27 | -89552 |
| 28 | 117632 |
| 29 | -153836 |
| 30 | 200352 |
| 31 | -259904 |
| 32 | 335872 |
| 33 | -432480 |
| 34 | 554952 |
| 35 | -709728 |
| 36 | 904784 |
| 37 | -1149916 |
| 38 | 1457136 |