# Finding the sum!

Algebra Level pending

If $$\displaystyle \sum_{r=0}^{3n}a_r$$$$(x-4)^r$$ = $$\displaystyle \sum_{r=0}^{3n}A_r$$$$(x-5)^r$$ and $$a_k$$ = 1 $$\forall k \geq 2n$$ and
$$\displaystyle \sum_{r=0}^{3n}d_r$$$$(x-8)^r$$ = $$\displaystyle \sum_{r=0}^{3n}B_r$$$$(x-9)^r$$ and
$$\displaystyle \sum_{r=0}^{3n}d_r$$$$(x-12)^r$$ = $$\displaystyle \sum_{r=0}^{3n}D_r$$$$(x-13)^r$$ and $$d_K$$ = 1 $$\forall k \geq 2n$$ .

Then find the value of $$(\frac{A_{2n} + D_{2n}}{B_{2n}}$$)

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