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تسجيل مستخدم جديدLimbs and Cospectral Vertices in Trees
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We generalize Schwenks result that almost all trees contain any given limb to trees with positive integer vertex weights. The concept of characteristic polynomial is extended to such weighted trees and we prove almost all weighted trees have a cospectral mate. We also prove almost all trees contain $k$ cospectral vertices for any integer $kge2$.
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