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) |
|---|---|
| 2 | 1 |
| 3 | -2 |
| 4 | 0 |
| 5 | 10 |
| 6 | -35 |
| 7 | 84 |
| 8 | -168 |
| 9 | 300 |
| 10 | -495 |
| 11 | 770 |
| 12 | -1144 |
| 13 | 1638 |
| 14 | -2275 |
| 15 | 3080 |
| 16 | -4080 |
| 17 | 5304 |
| 18 | -6783 |
| 19 | 8550 |
| 20 | -10640 |
| 21 | 13090 |
| 22 | -15939 |
| 23 | 19228 |
| 24 | -23000 |
| 25 | 27300 |
| 26 | -32175 |
| 27 | 37674 |
| 28 | -43848 |
| 29 | 50750 |
| 30 | -58435 |
| 31 | 66960 |
| 32 | -76384 |
| 33 | 86768 |
| 34 | -98175 |
| 35 | 110670 |
| 36 | -124320 |
| 37 | 139194 |
| 38 | -155363 |
| 39 | 172900 |