On matrix near-rings.
Let be a -prime left near-ring with multiplicative center , a -derivation on is defined to be an additive endomorphism satisfying the product rule for all , where and are automorphisms of . A nonempty subset of will be called a semigroup right ideal (resp. semigroup left ideal) if (resp. ) and if is both a semigroup right ideal and a semigroup left ideal, it be called a semigroup ideal. We prove the following results: Let be a
A class of semirings, so called p-semirings, characterized by a natural number p is introduced and basic properties are investigated. It is proved that every p-semiring is a union of skew rings. It is proved that for some p-semirings with non-commutative operations, this union contains rings which are commutative and possess an identity.