1: n=1, m=?
2: n=1, m=?  (n < 3): True
3: n=1, m=2
4: n=1, m=2  (m < 4): True
5: n=1, m=3
4: n=1, m=3  (m < 4): True
5: n=1, m=4
4: n=1, m=4  (m < 4): False
6: n=2, m=4
2: n=2, m=4  (n < 3): True
3: n=2, m=3
4: n=2, m=3  (m < 4): True
5: n=2, m=4
4: n=2, m=4  (m < 4): False
6: n=3, m=4
2: n=3, m=4  (n < 3): False
done