An ordered triple (a, b, c) is called a triangle triple if a, b, c are positive integers such that there is a triangle with side lengths a, b, c and a positive area.
find number of ordered triplet (a, b, c) such that a <= A, b <= B and c <= C
Input: A, B, C (all between 1 to 10^9)
Output: Number of triplets Mod 10^9 + 7
Problem: [Link]