2 papers
math.LO2018
Combinatorial principles equivalent to weak induction
Caleb Davis, Denis R. Hirschfeldt, Jeffry L. Hirst +3
We consider two combinatorial principles, and . Both are easily proved in plus induction. We give two proofs of in ${…
math.LO2018
Reverse mathematics and colorings of hypergraphs
Caleb Davis, Jeffry Hirst, Jake Pardo +1
Working in subsystems of second order arithmetic, we formulate several representations for hypergraphs. We then prove the equivalence of various vertex coloring theorems to ${\sf W…