Abstract: Let be a collection and be the set of allr-combinations of
distinct elements of X. Let Y be any nonempty subset of X
with cardinality k and let be the set of all that contains Y.
We extend the Bayer’s Theorem to the class of sets which is more general and give an
explicit formula for practical purposes.
Keywords and phrases: r-permutations, r-combinations, K-inclusion, K-non-inclusion.
