vector parallel to intersection of planes

The normal vector of the first plane is $\overrightarrow n _1 = 2{\mathbf{i}} - {\mathbf{j}} - 3{\mathbf{k}}
and the second is $\overrightarrow n _2 = {\mathbf{i}} + {\mathbf{j}} + {\mathbf{k}}$, note that they are linearly independent. So a vector parallel to the line of intersection of them is given by $\overrightarrow n _1 \times \overrightarrow n _2$