Pt1420 Unit 1 Math Paper

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We work with a Boolean Language whose basic symbols are $\vee,\wedge,\neg,\Rightarrow$ endowed with a finite set of atoms $\mathcal{A}$. The set of literals, $\mathcal{L}$, is the set $\mathcal{A}\cup\{\neg p|p\in\mathcal{A}\}$. A pair formed by a literal together with its negation is called a conjugated pair. Here we give the (classical) definition of valuation over a Boolean formula. That is the definition we will use henceforth. \begin{definition}\label{BOOLFOR:def} Given a finite set of {\em atoms}, $\mathcal{A}$, $\psi$ belongs to the set of Boolean formulas $\mathtt{F}$ if \begin{enumerate} \item $\psi\in\mathcal{A}$; \item $\psi=\chi\wedge\phi$ if both $\chi$ and $\phi$ belong to $\mathtt{F}$; \item $\psi=\chi\vee\phi$ if both $\chi$ …show more content…

\end{enumerate} \end{definition} \begin{definition}\label{VALUA:def} A valuation over a set of atoms $P$ is a mapping $v$ from $P$ to the set $\{True, False\}$ and, as usual, we extend the definition of $v$ to $v'$ as, \begin{enumerate} \item If $\psi\in\mathcal{A}$, $v'(\psi)=v(\psi)$; \item If $\psi=\chi\wedge\phi$, $v'(\psi)=True$ if …show more content…

The obvious, high consuming, expsize long search is a direct attempt to test all the $\mathbf{m}^{\mathbf{n}}$ trials. We refer to Example \ref{CARD:ex} for a card $\mathbf{3}\times\mathbf{2}$, a satisfiable one. Analogously to deciding Boolean formulas (satisfiable, unsatisfiable), we can, of course, solve cards and decide them all, but the game, likewise, is how fast can we solve a card. A card has $\mathbf{m}\times{\mathbf{n}}$ entries The number of disjunction in each entry is bounded by the maximum number of distinct disjunctions of at most two literals one can write given a finite number of atoms. In Section \ref{LASTIDEA:sec}, we discuss one effective, polynomially bounded, strategy. In Section \ref{BC:sec}, we discuss the complexity of the solution we gave. Here, we built the tools in order solve polynomially, in time and space, a card. The starting point is to define the cylindrical digraph associated with a given card. The vertices of a cylindrical digraph are associated with the disjunction of each entry. If $cl\equiv p\vee q$ is a disjunction of some entry, then both $\neg p\Rightarrow q$ and $\neg q\Rightarrow

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