Assignment #2
Due: Wednesday June 1
You will need to use some sort of computational aide for some of these problems. I've provided Sage cells with sample inputs below.
- Values of \(\phi\)
- Prove whether there are infinitely many values of \(\phi(n)\) that end in zero.
- Prove that for any positive integer \(t\), there exists a positive integer \(n\) such that the base 10 representation of \(\phi(n)\) ends with \(t\) zeros. Find one such integer where \(t=25\).
- Primitive Roots
- How many primitive roots are there mod 12251?
- Determine whether 10 and 11 are primitive roots mod 12251 using the criterion described in Algorithm 2.5.16 of Stein. Include a summary of the calculations you needed to do.
- Prove that an odd primitive root modulo an odd prime is still a primitive root for twice that modulus. ( This is a case I overlooked in describing the moduli that have primitive roots in class on May 23)
- (Stein 2.26) For every positive integer \(b\), show that there exists a positive integer \(n\) such that the polynomial \(x^2-1\) over \(Z/nZ\) has at least \(b\) roots
Sage Cell with input that computes modular powers
Sage Cell with inputs that compute \(\phi(n)\) and factors \(n-1\). You might not need to do both of these at once.
|