July 2026
Intermediate
270 pages
10h 6m
English
Content preview from Automata Theory and Formal Languages, 2nd Edition
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1 Preliminaries
This chapter offers all required prerequisites and elaborates on the notation used throughout the book. As such, the content presented here becomes helpful in the systematic exposure of the material covered in the consecutive chapters.
1.1 Sets
Finite sets include a finite number of members. The empty set, that is, the set which includes no members, is also finite. The empty set is denoted by ∅. Infinite sets include infinitely many members. Infinite sets are countable or uncountable.
We say that a set is countable if and only if its members could be arranged in a particular sequence. In other words, a set is countable if and only if we can enumerate (list) its members assigning natural numbers to them. Such an arrangement ...
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