Floyd Triangle Example Java Program

Definition

Floyd's triangle is a right-angled triangular array of natural numbers, used in computer science education. It is named after Robert Floyd. It is defined by filling the rows of the triangle with consecutive numbers, starting with a 1 in the top left corner

Formula

The nth row sums to n(n^2 + 1)/2

Floyd Triangle Example Program

import java.util.Scanner;
 
class FloydTriangle{
	public static void main(String args[]){
		int count, num = 1;
		Scanner in = new Scanner(System.in);
		System.out.print("Enter the number of rows:");
		count = in.nextInt();
		for (int i = 1 ; i <=count ; i++ ){
			for (int j = 1 ; j <= i ; j++ ){
				System.out.print(num+" ");
				num++;
			}
        System.out.println();
		}
	}
}

Sample Output

Output is:
Enter the number of rows:7
1
2 3
4 5 6
7 8 9 10
11 12 13 14 15
16 17 18 19 20 21
22 23 24 25 26 27 28