The magnitude of the projection of the vector $2\hat{\mathrm{i}}+3\hat{\mathrm{j}}+\hat{\mathrm{k}}$ on the vector perpendicular to the plan containing the vectors $\hat{\mathrm{i}}+\hat{\mathrm{j}}+\hat{\mathrm{k}}$ and $\hat{\mathrm{i}}+2\hat{\mathrm{j}}+3\hat{\mathrm{k}},$ is