How does this output 20?

Question

int i=0;
for(;i<5; i+=4)i=i*i;
printf("%d", i);

Answer 1

for i = 0;
i=0*0 = 0;
i+=4 = 4;

4<5 => True

for i = 4;
i=4*4 = 16;
i+=4 = 20;

20<5 => False