Perfect Number Program Java Methods(adsbygoogle = window.adsbygoogle || []).push({});

A perfect number is a positive integer equal to the sum of all its divisors (including 1 but excluding the number itself). For example:

28 = 1 + 2 + 4 + 7 + 14

According to Euclid, any solution to (2n-1) that results in a prime number will indicate that (2n-1)(2n-1) will be a perfect number. Thus, since 23-1 = 7, which is prime, 23-1(23-1) = 28, which is a perfect number. All even perfect numbers can be found in this fashion.

Write a program that will find the first n even perfect numbers, by testing the first formula to find primes, then using the second formula to find perfect numbers when the first reveals a prime answer. Use a long type rather than an int type to hold your responses. Find the first six perfect numbers.

This is what i got so far. please tell me what im doing wrong

/**

* @(#)perfectnumber.java

*

*

* @author

* @version 1.00 2011/11/27

*/

import java.util.Scanner;

public class perfectnumber {

public static void main (String args[])

{

Scanner input = new Scanner(System.in);

int Number;

int Sum=0;

System.out.println("Place an interger in the range of 2 to 100");

Number=input.nextInt();

if(Number<2 || Number>100){

System.out.println("Number does not match the range!");

}

else

for(int i=2; i<Number; i++)

{

for(int j=1; j<i; j++){

if(i%j==0) //i mod j=0

Sum+=j; //part of the sum

}

if(Sum==i){

System.out.println("Perfect Number:" + i);

for(int factor=1; factor<1; factor++){

if(i%factor==0)

System.out.print(factor + "+");

}

System.out.println("="+ i);

}

Sum=0;

}

}

}

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# Homework Help: Hi i need help with this perfect number program! Please help

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