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 | 0 |
| 1 | -1 |
| 2 | 9 |
| 3 | -25 |
| 4 | 55 |
| 5 | -100 |
| 6 | 166 |
| 7 | -254 |
| 8 | 370 |
| 9 | -515 |
| 10 | 695 |
| 11 | -911 |
| 12 | 1169 |
| 13 | -1470 |
| 14 | 1820 |
| 15 | -2220 |
| 16 | 2676 |
| 17 | -3189 |
| 18 | 3765 |
| 19 | -4405 |
| 20 | 5115 |
| 21 | -5896 |
| 22 | 6754 |
| 23 | -7690 |
| 24 | 8710 |
| 25 | -9815 |
| 26 | 11011 |
| 27 | -12299 |
| 28 | 13685 |
| 29 | -15170 |
| 30 | 16760 |
| 31 | -18456 |
| 32 | 20264 |
| 33 | -22185 |
| 34 | 24225 |
| 35 | -26385 |
| 36 | 28671 |
| 37 | -31084 |
| 38 | 33630 |
| 39 | -36310 |
| 40 | 39130 |