Centros al cuadrado RANDOM Gen

import java.util.Scanner;

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/**
 *
 * @author Uriel
 */
public class MetodosCuadrados {

    public static void main(String[] args) {
        Scanner xr = new Scanner(System.in);
        int n;
        int semilla;

        System.out.println("Iteracciones");

        n = xr.nextInt();

        System.out.println("Semilla");
        semilla = xr.nextInt();

        for (int i = 0; i < n; i++) {

            int cuadrado = semilla*semilla;
            String cuad = cuadrado+"";

            if(cuad.length()%2 != 0){
                cuad = "0"+cuad;
            }

            String centro = cuad.substring( ((cuad.length()/2)-2), (((cuad.length()/2)-2)+4));

            double uniforme = Double.parseDouble(centro) / 10000;


            System.out.println("Iteraccion: "+(i+1)+" Numero "+semilla+"  Cuadrado  "+cuad+"  Centro "+centro+"  "+" Uniforme  "+uniforme);

            semilla = Integer.parseInt(centro);
        }


    }

}