Type-one tree complement conjecture for multiplicity bipartition

Let T=Sm,nkT=S^k_{m,n} be the tree formed by taking a path on kk vertices and adding mm leaves to one endpoint and nn leaves to the other, where kin{2,3,4}kin\{2,3,4\} and m,n>1m,n>1. Write q(G)q(G) for the minimum number of distinct eigenvalues of a graph GG, and MB(G)MB(G) for its multiplicity bipartition. Type-one tree complement conjecture. Then q(T)=2q(\overline{T})=2 and MB(T)=3MB(\overline{T})=3. The conjecture concerns a family of complements of type-one trees and asserts both the two-eigenvalue property and the specified multiplicity bipartition; the surrounding discussion presents these as open problems.

Sources & referencesView supporting material

Primary source

Mohammad Adm, Shaun Fallat, Karen Meagher, Shahla Nasserasr, Sarah Plosker and Boting Yang, “Achievable multiplicity partitions in the inverse eigenvalue problem of a graph”, arXiv:1907.11328 (2020).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.