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# Article

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Keywords:
cardinal functions; cardinal inequalities
Summary:
The main goal of this paper is to establish a technical result, which provides an algorithm to prove several cardinal inequalities and relative versions of cardinal inequalities related to the well-known Arhangel'skii's inequality: If $X$ is a $T_2$-space, then $|X|\leq 2^{L(X)\chi (X)}$. Moreover, we will show relative versions of three well-known cardinal inequalities.
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