101622: [AtCoder]ABC162 C - Sum of gcd of Tuples (Easy)
Memory Limit:256 MB
Time Limit:2 S
Judge Style:Text Compare
Creator:
Submit:1
Solved:0
Description
Score : $300$ points
Problem Statement
Find $\displaystyle{\sum_{a=1}^{K}\sum_{b=1}^{K}\sum_{c=1}^{K} \gcd(a,b,c)}$.
Here $\gcd(a,b,c)$ denotes the greatest common divisor of $a$, $b$, and $c$.
Constraints
- $1 \leq K \leq 200$
- $K$ is an integer.
Input
Input is given from Standard Input in the following format:
$K$
Output
Print the value of $\displaystyle{\sum_{a=1}^{K}\sum_{b=1}^{K}\sum_{c=1}^{K} \gcd(a,b,c)}$.
Sample Input 1
2
Sample Output 1
9
$\gcd(1,1,1)+\gcd(1,1,2)+\gcd(1,2,1)+\gcd(1,2,2)$ $+\gcd(2,1,1)+\gcd(2,1,2)+\gcd(2,2,1)+\gcd(2,2,2)$ $=1+1+1+1+1+1+1+2=9$
Thus, the answer is $9$.
Sample Input 2
200
Sample Output 2
10813692