Open quipus with the same Wiener index as their quadratic line graph
نویسندگان
چکیده
We show that graph equation W (L(T )) = W (T ), where T is a tree, W (T ) its Wiener index and L(T ) its line graph, has infinitely many nonhomeomorphic solutions among open quipus. This gives a positive answer to the 2004 problem of Dobrynin and Mel’nikov on the existence of solutions with arbitrarily large number of arbitrarily long pendant paths, and disproves the 2014 conjecture of Knor and Škrekovski.
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ورودعنوان ژورنال:
- Applied Mathematics and Computation
دوره 281 شماره
صفحات -
تاریخ انتشار 2016