I don't know if you mean the logic notation often seen in programming language papers, but it's called sequent calculus. Wikipedia page has a good intro and lin

I don't know if you mean the logic notation often seen in programming language papers, but it's called sequent calculus. Wikipedia page has a good intro and links to further resources: https://en.m.wikipedia.org/wiki/Sequent_calculus https://en.m.wikipedia.org/wiki/Sequent_calculus