Ngày tải lên :
31/05/2014, 00:58
... abab}, and {aa, ab, aab, ba, bb, bab} The first of these is the union of {a} and {b}, the second is the concatenation of {a} and {b}, the third is the union of the first and second, the fourth is the ... (n) is the set of prime factors of n e (Here A is the set of all finite sets of primes and B is the set N − {0}.) g : A → B, where g(S) is the product of the elements of S (The product of the elements ... sets {0, 1} and {1, 0} are the same, because both contain the elements and and no others; the set {0, 0, 1, 1, 1, 2} is the same as {0, 1, 2}, because they both contain 0, 1, and and no other elements...