\[\lim_{n \to \infty} \dfrac{\displaystyle\sum abcde}{n^{10}}=\dfrac{A}{B}\]
subject to the condition that \(1 \leq a \leq b \leq c \leq d \leq e \leq n\). Find \(A+B\).
\(\textbf{Note :} \ A,B\) are co-prime integers. The answer is exact, not an approximation.