Let P be the plane passing through the points $(5,3,0),(13,3,-2)$ and $(1,6,2)$. For $\mathrm{\alpha }\in \in \mathrm{\mathbb{N}}$, if the distances of the points $\text{A}(3,4,\mathrm{\alpha })$ and $\text{B}(2,\mathrm{\alpha },\mathrm{a})$, from the plane P are 2 and 3 respectively, then the positive value of a is