Prove that a tree has at least two vertices of degree 1.
127277
Graph Theory: Tree has at least 2 vertices of degree 1
7626
Proving that every connected graph has a vertex whose removal will not disconnect the graph.
35458
Prove, that graph $G$ has at least $\chi(G)(\chi(G)-1)/2$ edges.
157939
prove that a graph is one-ended
1409
Proving that the given set has at most $2^{n-1}$ elements
10910
How many edges does an undirected tree with $n$ nodes have?
129752
How to find whether it is possible for each vertex of a graph to have a different degree?
59831
How to relate combinatorial proof to bipartite graphs?
158083
If $G$ is a connected graph with $n$ vertices and $n - 1$ edges then $G$ is a tree, using Induction.
158802
Graph theory and tree company
146933
Proving bipartition in a connected planar graph
49045
Graph theory: Tree holds two sub-tree with an amount of vertices
158856
Prove that a graph with the same number of edges and vertices contains one cycle
97630
A graph which is not a single block has at least two leaf blocks
117992
Help with graph induction proof
142809
Trees whose complement is also a tree
129845
Prove that $T$ is a subgraph of $G$