At first glance, having no information on this other than a title and an image, I assumed there was some data encoded in the odd pattern on the flags at the top of the tombstone. I then read through the article waiting to learn what was there, and of course it was never mentioned.
A google search turned up a higher-resolution photo of the tombstone: http://elonka.com/friedman/Tombstone.JPG
The lines on the flags appear to be ordinary stripes, with nothing encoded in them. So I guess I can thank my own imagination for turning an otherwise fascinating story into a bit of a disappointment.