The degree of every vertex of a graph G of order $\displaystyle 2n+1 \geq 5 $ is either n+1 or n+2. Prove that G contains at least n+1 vertices of degree n+2 or at least n+2 vertices of degree n+1
The degree of every vertex of a graph G of order $\displaystyle 2n+1 \geq 5 $ is either n+1 or n+2. Prove that G contains at least n+1 vertices of degree n+2 or at least n+2 vertices of degree n+1