public class Pyramid
{
    public static void main(String[] args)
    {
        int i=0,j=0,n=6,k=0;
        for(i=0; i<n; i++)
        {
            k=1;
            for(j=0; j<(n+i); j++)
            {
               if(j<n-i-1)
                    System.out.print(" ");
                else
                {
                    System.out.print(""+k);
                    if(j<(n-1))
                        k++;

                    else
                        k--;
                }
            }
            System.out.println(" ");
        }
    }

}

 OUTPUT

 

     1
    121
   12321
  1234321
 123454321
12345654321