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) |
|---|---|
| 1 | 1 |
| 2 | -2 |
| 3 | 4 |
| 4 | -8 |
| 5 | 14 |
| 6 | -24 |
| 7 | 40 |
| 8 | -64 |
| 9 | 101 |
| 10 | -156 |
| 11 | 236 |
| 12 | -352 |
| 13 | 518 |
| 14 | -752 |
| 15 | 1080 |
| 16 | -1536 |
| 17 | 2162 |
| 18 | -3018 |
| 19 | 4180 |
| 20 | -5744 |
| 21 | 7840 |
| 22 | -10632 |
| 23 | 14328 |
| 24 | -19200 |
| 25 | 25591 |
| 26 | -33932 |
| 27 | 44776 |
| 28 | -58816 |
| 29 | 76918 |
| 30 | -100176 |
| 31 | 129952 |
| 32 | -167936 |
| 33 | 216240 |
| 34 | -277476 |
| 35 | 354864 |
| 36 | -452392 |
| 37 | 574958 |
| 38 | -728568 |
| 39 | 920600 |