Write a program in Java to print a numbers from Tribonacci series

A tribonacci series is one in which the sum next term is the sum of previous three terms eg. 0    1   2  3    6     11    20

public class Tribonacci
    {
   public static void main(String args[])
     {
      int a=0, b=1, c= 2, d=0;
      System.out.print( a +"  "+ b + "  "+ c);
      for(int i=1;i<=10;i++)
        {
         d=a+b+c;
         System.out.print("  "+ d);
         a=b;
         b=c;
         c=d;
        }
      }
    }

Output: 
0  1  2  3  6  11  20  37  68  125  230  423  778