MATLAB: Prime number.there isn’t any error. the ans isn’t showed up

Question

% finding prime number
counter=0;
for j= 1:10;
   for i=1:1:j
       if mod (j,i)==0
           counter=counter+1;
       end
   end
  if counter==2
    fprintf('%d is prime', j);
  end
end

there isn't any error. my ans isn't showed up

Answer 1

There is actually one error (where counter is reset)

for j= 1:10
    counter=0; % <- reset for every i to be checked
    for i=1:1:j
        if mod (j,i)==0
            counter=counter+1;
        end
    end
    if counter==2
        fprintf('%d is prime\n', j);
    end
end