Modular Cubes, part 2
Problem 272
Published on Saturday, 2nd January 2010, 05:00 am; Solved by 519
For a positive number n, define C(n) as the number of the integers x, for which 1
xn and
x3
1 mod n.
When n=91, there are 8 possible values for x, namely : 9, 16, 22, 29, 53, 74, 79, 81.
Thus, C(91)=8.
Find the sum of the positive numbers n
1011 for which C(n)=242.