wrong output when reading a file with fscanf

[Lokinyx]

% create an file
fID1 = fopen('myoutput1.txt','w');
for n = 1:4
b1 = n; b2 = n^2; b3 = n^3;
fprintf(fID1,'%7u %7u %7u \r',b1,b2,b3);
end
fclose(fID1);

% then reopen it
fID1 = fopen('myoutput1.txt','r');
for n = 1:4
b = fscanf(fID1,'%7u %7u %7u \r',3)
end
fclose(fID1);

I expect the output:
b =

 1
 1
 1

b =

 2
 4
 8

b =

 3
 9
27

b =

 4
16
64

but from Nelson I get
b =

 []

b =

 []

b =

 1

b =

 []