Goldbach’s Weak Conjecture for Odd numbers

Given an odd number N, the task is to find if the number can be represented as the sum of 3 prime numbers.
Examples:

Input: N = 7
Output: Yes
Explanation:
2 + 2 + 3 = 7

Input: N = 17
Output: Yes
Explanation:
2 + 2 + 13 = 17

Approach:
In number theory, Goldbach’s weak conjecture, also known as the odd Goldbach conjecture, the ternary Goldbach problem, or the 3-primes problem, states that Every odd number greater than 5 can be expressed as the sum of three primes. (A prime may be used more than once in the same sum.).
Below is the implementation of the above approach: 

C++

// C++ implementation of the approach
#include <bits/stdc++.h>
using namespace std;

// if a number can
// be represent as
// as a sum of 3 prime
void check(int n)
{
    if (n % 2 == 1 && n > 5)
        cout << "Yes\n";
    else
        cout << "No\n";
}

// Driver code
int main()
{
    int a = 3;
    int b = 7;
    check(a);
    check(b);
    return 0;
}

// This code is contributed by 29AjayKumar

Java

class GFG
{
    // Function to check
    // if a number can
    // be represent as
    // as a sum of 3 prime

    static void check(int n)
    {
        if (n % 2 == 1 && n > 5)
        {
            System.out.println("YES");
        }
        else
        {
            System.out.println("NO");
        }
    }

    // Driver code
    public static void main(String[] args)
    {
        int a = 3;
        int b = 7;
        check(a);
        check(b);
    }
}

// This code is contributed by PrinciRaj1992

Python3

# Function to check
# if a number can
# be represent as
# as a sum of 3 prime
def check(n):
  if n % 2 == 1 and n > 5:
    print('YES')
  else:
    print('NO')

# Driver code
def main():
  a = 3
  b = 7
  check(a)
  check(b)

main()

C#

using System;
class GFG
{
    // Function to check
    // if a number can
    // be represent as
    // as a sum of 3 prime

    static void check(int n)
    {
        if (n % 2 == 1 && n > 5)
        {
            Console.Write("YES");
        }
        else
        {
            Console.WriteLine("NO");
        }
    }

    // Driver code
    public static void Main(String[] args)
    {
        int a = 3;
        int b = 7;
        check(a);
        check(b);
    }
}

// This code is contributed by PrinciRaj1992

Javascript

    // Function to check
    // if a number can
    // be represent as
    // as a sum of 3 prime

    function check(n)
    {
        if (n % 2 == 1 && n > 5)
        {
            document.write("YES");
        }
        else
        {
            document.write("NO" + "<br>");
        }
    }

    // Driver code

        var a = 3;
        var b = 7;
        check(a);
        check(b);


// This code is contributed by shivanisinghss2110

Output:

NO
YES

Time Complexity: O(1)

Auxiliary Space: O(1)