The null space for the matrix $\left[\begin{array}{ccc} 2 &0 &5\cr -1 &6 &2\cr 4 &4 &-1\cr 5 &1 &0\cr 4 &1 &1 \end{array}\right]$
is spanned by the vector $\left[\Rule{0pt}{3.6em}{0pt}\right.$$\left]\Rule{0pt}{3.6em}{0pt}\right.$,