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 | -5 |
| 2 | 10 |
| 3 | -15 |
| 4 | 30 |
| 5 | -55 |
| 6 | 80 |
| 7 | -120 |
| 8 | 190 |
| 9 | -285 |
| 10 | 410 |
| 11 | -585 |
| 12 | 840 |
| 13 | -1190 |
| 14 | 1640 |
| 15 | -2240 |
| 16 | 3070 |
| 17 | -4170 |
| 18 | 5570 |
| 19 | -7400 |
| 20 | 9830 |
| 21 | -12960 |
| 22 | 16920 |
| 23 | -21990 |
| 24 | 28520 |
| 25 | -36805 |
| 26 | 47180 |
| 27 | -60225 |
| 28 | 76720 |
| 29 | -97350 |
| 30 | 122880 |
| 31 | -154610 |
| 32 | 194110 |
| 33 | -242880 |
| 34 | 302740 |
| 35 | -376295 |
| 36 | 466710 |
| 37 | -577270 |
| 38 | 711800 |