Let A be a point on the line $\overrightarrow{\mathrm{r}}=\left(1-3\mathrm{\mu }\right)\widehat{\mathrm{i}}+\left(\mathrm{\mu }-1\right)\widehat{\mathrm{j}}+\left(2+5\mathrm{\mu }\right)\widehat{\mathrm{k}}$  and  $\mathrm{B}\left(3,2,6\right)$ be a point in the space. Then the value of  $\mathrm{\mu }$ for which the vector  $\overrightarrow{\mathrm{AB}}$ is parallel to the plane  $\mathrm{x}-4\mathrm{y}+3\mathrm{z}=1$ is