Piecewise syndetic set

In mathematics, piecewise syndeticity is a notion of largeness of subsets of the natural numbers.

is called piecewise syndetic if there exists a finite subset G of

Equivalently, S is piecewise syndetic if there is a constant b such that there are arbitrarily long intervals of

where the gaps in S are bounded by b.

There are many alternative definitions of largeness that also usefully distinguish subsets of natural numbers: