I know it was in a Fons & Porter mag a few yrs ago. I think someone on here made one,but I'd never be able to find it in search. Sorry- Guess I'm not too helpful.............
I think you might be able to figure it out by yourself. If you look at the bottom of the black rows, you can see how the pattern is made. The 1st block in the row is the square with the strips going around it. The next block is the stripes in between. Then there seems to be the thinner sashing row in between the larger blocks. Looks like the 1st & last of the white pieces is wider in the 2nd,etc, bigger block rows.That's really all there is to it. Just decide how big you want it & do the math. Alternate the blocks. Don't forget the seam allowances. Good luck on the search.
PS- I use graph paper to figure things like this out.