\[\boxed{\mathbf{1582}\mathbf{.}}\]
\[\log_{b}a \bullet \log_{c}b \bullet \log_{d}c = \log_{d}a\]
\[\log_{b}a \bullet \log_{c}b \bullet \log_{d}c =\]
\[= \frac{\log_{c}a}{\log_{c}b} \bullet \log_{c}b \bullet \log_{d}c =\]
\[= \log_{c}a \bullet \log_{d}c =\]
\[= \frac{\log_{d}a}{\log_{d}c} \bullet \log_{d}c = \log_{d}a.\]
\[Тождество\ доказано.\]