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seen Dec 14 '12 at 13:44

Dec
13
asked How do you find a subset D of set A such that |D| > |N(D)| in a bipartite graph with bipartition A, B (or prove that no such set exist)?
Dec
12
accepted Proof related to breadth first search
Dec
12
revised Proof related to breadth first search
deleted 2 characters in body
Dec
12
asked Proof related to breadth first search
Dec
12
awarded  Scholar
Dec
12
accepted Hint on proving this inequality for a planar graph?
Dec
12
comment Hint on proving this inequality for a planar graph?
Ah, I got it! $t + 6(p-t) \le 2q$ Thank you!
Dec
11
awarded  Editor
Dec
11
revised Hint on proving this inequality for a planar graph?
added 78 characters in body
Dec
11
comment Hint on proving this inequality for a planar graph?
Sorry - (i) is an identity for connected planar graph with p >=3 vertices and q edges. (ii) Euler's formula: Let G be a connected graph with p vertices and q edges. If G has a planar embedding with f faces, then p - q + f = 2. (f = 1 in this case with only 1 outer face for a tree).
Dec
11
awarded  Student
Dec
11
asked Hint on proving this inequality for a planar graph?