MathCastle
Number TheorySuperchallengeOrders and Primitive Roots

Orders and Primitive Roots · Superchallenge problem

How many integers xx with 1≤x≤10001 \le x \le 1000 and gcd⁡(x,1001)=1\gcd(x, 1001) = 1 have order exactly 3030 modulo 1001=7⋅11⋅131001 = 7 \cdot 11 \cdot 13?