If A Is An Arbitrary Integer, We Define A Subset [A] Of Z As Follows: N=Ua . In Other Words, [A] Is The Set Of All Integers That Are Multiples Of A If A, B Are Arbitrary Integers, We Define A Subset [A Of Z As Follows: N=Ua + Ub In Other Words, [A, B Is The Set Of All Integers That Are The Sum Of A Multiple Of A And A Multiple Of B. Equivalently, [A, B] Is