5 1 4
5 -1 4 = 3 1 2
3 1 2
3 -1 2 = 1
5 -1 4 = 3 1 2
3 -1 2 = 1

 
Correct unknotting number u(5 1 4) = 2 obtained from the minimal projection of the knot 5 1 4.