Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Common equivalence and size after forgetting   Forgetting variables from a propositional formula may increase its size.
Introducing new variables is a way to shorten it. Both operations can be
expressed in terms of common equivalence, a weakened version of equivalence. In
turn, common equivalence can be expressed in terms of forgetting. An algorithm
for forgetting and checking common equivalence in polynomial space is given for
the Horn case; it is polynomial-time for the subclass of single-head formulae.
Minimizing after forgetting is polynomial-time if the formula is also acyclic
and variables cannot be introduced, NP-hard when they can.

27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
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The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an