alternating rhythm!

( I found this picture from internet.)
I think this might be a sample of alternating rhythm. The conception of "alternating rhythm " is defined by consisting of successive patterns in which the same elements reappear in a regular order. (from a book, named <>. Author is : David A. Lauer Stephen Pentak.) The repeating pattern of the iron shapes against negative space shows this type of rhythm. The design involves a sequence of forms from center to outsides catching our attention.