Error in printing series 1, (1+1)^2= 4, (4+1)^2 =25 upto 10 terms.

Error in printing series 1 , (1+1)^2= 4 , (4+1)^2 =25 upto 10 terms.
Code:

integer i , n1=1 , n2=1 , n3=2 , n4=1 , count=10;
for(i=0;i<count;i++)
{
n4 = (n1+n2)*(n1+n2);
System.debug(n1 + ', (' + n1 + '+' + n2 + ')^' + n3 + '=' + n4 + ' , ');
n1=n4;
}

Screenshot:

debug in different lines not in a single line . How to debug in a single line like a whole series?