Let

be the Proth-Gilbreath operator that
transforms a sequence of integers into the sequence of the absolute
values of the differences between all pairs of neighbor terms.
Consider the infinite tables obtained by successive iterations of

applied to different initial sequences of
integers.
We study these tables of higher order differences and characterize
those that have near-periodic features.
As a biproduct, we also obtain two results on a class of formal
power series over the field with two elements

that
can be expressed as rational functions in several ways.