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\begin{center} {\bf Corrections etc}\end{center}
\vspace{2\baselineskip}
Note the two changes in the syllabus introduced last year.

(1) Secret sharing introduced. 

(2) You now need to be able to give an informal
account of quantum cryptography.

Note also that the Shannon's theorems in the syllabus
are those given in the notes. Some earlier lecturers
went deeper into entropy than this lecturer and there
are one or two earlier exam questions which go beyond
what will be done in the present course.

The abreviation GVS should be replaced by GSV where
it occurs. (I think page 27 only.) 

\vspace{2\baselineskip}

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