please show converse as well 20, Let p be prime. Show that p X n, where...
Problem 7. Let M = 2" – 1, where n is an odd prime. Let p be any prime factor of M. Prove that p=n·2j + 1 for some positive integer j.
5a. Show that in Zp, p prime, the only elements that are self-inverses (ie. elements [a] such that [a]. [a] = [1]) are [1] and [p 1 b. In Zp, p prime, show that [p-1)!] [-1]. This result is known as Wilson's Theorem. c. Show that if n is a positive integer greater than 1 and [(n-1)!] = [-1] in Zn, then n is prime. This is the converse of Wilson's Theorem.
Show that if G is a group of order np where p is prime and 1 <n<p, then G is not simple.
Let n be a positive integer. Show that nº + 4n +5 has no prime divisor p with p 3 mod 4.
8. (a) Prove that if p and q are prime numbers then p2 + pq is not a perfect square. (b) Prove that, for every integer a and every prime p, if p | a then ged(a,pb) = god(a,b). Is the converse of this statement true? Explain why or why not. (c) Prove that, for every non-zero integer n, the sum of all (positive or negative) divisors of n is equal to zero. 9. Let a and b be integers...
12 ) - 2. Let p(n) denote the number ofdstinct prime divisors ofn. For example, p( p(24)-2 and p(60) 3. Let q(n)an, where a is fixed and show that qn) is multiplicative, but not completely multiplicative. 12 ) - 2. Let p(n) denote the number ofdstinct prime divisors ofn. For example, p( p(24)-2 and p(60) 3. Let q(n)an, where a is fixed and show that qn) is multiplicative, but not completely multiplicative.
1. Suppose that X, X, X, are iid Berwulli(p),0 <p<1. Let U. - x Show that, U, can be approximated by the N (np, np(1-P) distribution, for large n and fixed <p<1. 2. Suppose that X1, X3, X. are iid N ( 0°). Where and a both assumed to be unknown. Let @ -( a). Find jointly sufficient statistics for .
Let P, Q ∈ Z[x]. Prove that P and Q are relatively prime in Q[x] if and only if the ideal (P, Q) of Z[x] generated by P and Q contains a non-zero integer (i.e. Z ∩ (P, Q) ̸= {0}). Here (P, Q) is the smallest ideal of Z[x] containing P and Q, (P, Q) := {αP + βQ|α, β ∈ Z[x]}. (iii) For which primes p and which integers n ≥ 1 is the polynomial xn − p...
Part 15A and 15B (15) Let n E Z+,and let d be a positive divisor of n. Theorem 23.7 tells us that Zn contains exactly one subgroup of order d, but not how many elements Z has of order d. We will determine that number in this exercise. (a) Determine the number of elements in Z12 of each order d. Fill in the table below to compare your answers to the number of integers between 1 and d that are...
10. Let [n] be an element in Zp, p prime. We say [n] is perfect provided [o (n)] [2n]. Show that d-[21,where Idy]-'is the multiplicative inverse of ld in Z, [dkl In 10. Let [n] be an element in Zp, p prime. We say [n] is perfect provided [o (n)] [2n]. Show that d-[21,where Idy]-'is the multiplicative inverse of ld in Z, [dkl In