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\title{\LaTeX test}

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\subsection*{Problem 4} % (fold)
\label{sub:problem_4}
.... Here we denote with $A_\mathfrak{p}$ the localization of $A$ w.r.t to the multiplicative set $A\setminus{}\mathfrak{p}$. Note that $g \in A\setminus{}\mathfrak{p}$, since $\mathfrak{p} \in D(g)$ just means $g \not\in \mathfrak{p}$ The rather lengthy condition above just means in a nutshell, that the elements of $\mathcal{O}(U)$ are just the local fractions of \glqq{}functions\grqq{}: An element $f \in A$ can be viewed as a function on $\operatorname{Spec}(A)$, by means of the mapping 
% subsection problem_4 (end)

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