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 | 14 |
| 5 | -24 |
| 6 | 40 |
| 7 | -64 |
| 8 | 100 |
| 9 | -154 |
| 10 | 232 |
| 11 | -344 |
| 12 | 504 |
| 13 | -728 |
| 14 | 1040 |
| 15 | -1472 |
| 16 | 2062 |
| 17 | -2864 |
| 18 | 3948 |
| 19 | -5400 |
| 20 | 7336 |
| 21 | -9904 |
| 22 | 13288 |
| 23 | -17728 |
| 24 | 23528 |
| 25 | -31066 |
| 26 | 40824 |
| 27 | -53408 |
| 28 | 69568 |
| 29 | -90248 |
| 30 | 116624 |
| 31 | -150144 |
| 32 | 192612 |
| 33 | -246256 |
| 34 | 313808 |