[不等式] How to holder it?

Let $ a,b,c$ be positive real numbers. Prove that:
\[ \left(\dfrac{a}{13a+17b}\right)^{\frac{2}{5}}+\left(\dfrac{b}{13b+17c}\right)^{\frac{2}{5}}+\left(\dfrac{c}{13c+17a}\right)^{\frac{2}{5}}\le\dfrac{3}{30^{\frac{2}{5}}} \]

五次……不知该配啥好了