Let a_1=b_1=1 and a_n=a_n-1+(n-1), b_n=b_n-1+a_n-1, ∀ n ≥ 2. If S=Σ_n=1^10 b_n/2^n and T =Σ_n=1^8 n/(2^n-1), then 2^7(2 S- T ) is equal to ____.

Let $\displaystyle a_1=b_1=1$ and $\displaystyle a_n=a_{n-1}+(n-1), b_n=b_{n-1}+a_{n-1}, \forall n \geq 2$. If $\displaystyle S=\sum_{n=1}^{10} \frac{b_n}{2^n}$ and $\displaystyle \mathrm{T}=\sum_{n=1}^8 \frac{n}{2^{n-1}}$, then $\displaystyle 2^7(2 S-\mathrm{T})$ is equal to $\displaystyle \_\_\_\_$.