Let \( I_{n}=\displaystyle\int_{1}^{e}x^{19}(\log |x|)^{n}\,dx \), where \( n\in \mathbb{N} \). If \( (20)\,I_{10}= \alpha I_{9}+\beta I_{8} \) for natural numbers \( \alpha \) and \( \beta \), then \( \alpha-\beta \) equals to ________.
