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 | 1 |
| 4 | -4 |
| 5 | 10 |
| 6 | -10 |
| 7 | 12 |
| 8 | -24 |
| 9 | 37 |
| 10 | -44 |
| 11 | 56 |
| 12 | -84 |
| 13 | 126 |
| 14 | -160 |
| 15 | 186 |
| 16 | -272 |
| 17 | 394 |
| 18 | -466 |
| 19 | 568 |
| 20 | -792 |
| 21 | 1052 |
| 22 | -1272 |
| 23 | 1560 |
| 24 | -2040 |
| 25 | 2663 |
| 26 | -3244 |
| 27 | 3877 |
| 28 | -4992 |
| 29 | 6410 |
| 30 | -7644 |
| 31 | 9180 |
| 32 | -11616 |
| 33 | 14472 |
| 34 | -17284 |
| 35 | 20712 |
| 36 | -25572 |
| 37 | 31518 |
| 38 | -37576 |
| 39 | 44510 |
| 40 | -54416 |
| 41 | 66402 |
| 42 | -78368 |
| 43 | 92648 |