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 | 3 |
| 3 | -8 |
| 4 | 15 |
| 5 | -24 |
| 6 | 39 |
| 7 | -64 |
| 8 | 102 |
| 9 | -152 |
| 10 | 225 |
| 11 | -336 |
| 12 | 492 |
| 13 | -700 |
| 14 | 987 |
| 15 | -1392 |
| 16 | 1941 |
| 17 | -2664 |
| 18 | 3630 |
| 19 | -4936 |
| 20 | 6660 |
| 21 | -8896 |
| 22 | 11817 |
| 23 | -15648 |
| 24 | 20604 |
| 25 | -26942 |
| 26 | 35070 |
| 27 | -45512 |
| 28 | 58800 |
| 29 | -75576 |
| 30 | 96777 |
| 31 | -123568 |
| 32 | 157206 |
| 33 | -199200 |
| 34 | 251613 |
| 35 | -316992 |
| 36 | 398148 |
| 37 | -498460 |
| 38 | 622356 |
| 39 | -775216 |