Pronic Number Program in Java

In this post we will learn about the pronic number program in java. In this post I will be sharing what is pronic number, algorithm , java program  and points to remember about pronic number.

What is Pronic Number

A pronic number is a number which is represented by the product of two consecutive numbers , that is a number of the form "n x (n+1)". They are also called rectangular numbers, oblong numbers and heteromecic numbers.

Examples :

Number to check : 12
3 x 4 = 12  // 12 is a pronic number

Number to check : 20 

4 x 5 = 20  // 20 is a pronic number

Number to check : 30 

5 x 6 = 30  // 30 is a pronic number   

Number to check : 48

6 x 8 = 48  // 48 is not a pronic number  

Pronic numbers upto 100 are : 0, 2, 6, 12, 20, 30, 42, 56, 72, 90 etc.

Read Also :  Happy Number Program in Java

Algorithm to find Pronic Number

1. Check number N is pronic or not.
2. Calculate the square root K of the given number N.
3. Multiply K * (K+1), if result is equal to the  number N, then N is a pronic number otherwise not.

Java Program to find Pronic Number

import java.util.*;
public class JavaHungry { 

    public static void main(String args[]) { 

        System.out.println("Enter input number ");
        Scanner sc = new Scanner(System.in);
        int inputNumber = sc.nextInt();        
        int sqrtNum = (int) Math.sqrt(inputNumber);
        int product = sqrtNum * (sqrtNum + 1);
        if (product == inputNumber)
            System.out.println("Pronic Number");
        else
            System.out.println("Not a Pronic Number"); 

   }
}

Output :
Enter input number : 12
Pronic Number
 

Points to Remember :

1.  According to Wikipedia, all pronic numbers are even. 2 is the only prime pronic number.

2.  If number 25 is appended to the decimal representation of any pronic number, the outcome will always be a square number.

Examples : 
625 = 25²     // 6 is a pronic number , 25 appended = 625 is a square number.
1225 = 35²  // 12 is a pronic number , 25 appended = 1225 is a square number.

That's all for today, please mention in comments if you know any other way to check pronic number in java.