In
structural proof theory, the nested sequent calculus is a reformulation of the
sequent calculus
In mathematical logic, sequent calculus is a style of formal logical argumentation in which every line of a proof is a conditional tautology (called a sequent by Gerhard Gentzen) instead of an unconditional tautology. Each conditional tautolog ...
to allow
deep inference.
References
Proof theory
Logical calculi
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