However, (if gcd(n,a) = 1)
Hello I can't quite seem how to finish this problem:
The number 3750 satisfies f(3750) = 1000. Find a number a that has the following three properties:
(i) a º 7^3003 (mod 3750).
(ii) 1 < a < 5000.
(iii) a is not divisible by 7.