-4/{(k+1)(k-1)pi} . cos(kwt) , k is even
The mean value is 0.637 and the following table gives the first few non- zero cosine terms:
| Cosine frequency, w | Contribution |
| 2 | -0.424 |
| 4 | -0.085 |
| 6 | -0.036 |
| 8 | -0.020 |
| 10 | -0.013 |
The expansion for a fully rectified sinewave is essentially the same, as long as its peak amplitude is considerably higher than a couple of diode drops. In particular, the term in sin(wt) is missing: This is no surprise, since this component is doing exactly as expected for half the cycle, but precisely the opposite for the other half of the cycle.
The fractal images can now be downloaded.