Does there exists any simple connected graph G of order n, such that whenever λk is an eigenvalue of the adjacency matrix of G

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anonymous user

Anonymous

updated 0 years ago

FrédéricC gravatar image

Does there exists any simple connected graph G of order n, such that whenever λk is an eigenvalue of the adjacency matrix of G, kλ is also an eigenvalue of adjacency matrix of G. Here k is any positive natural number (k=1,2,3,4,5,) and λ(0) is an eigenvalue of adjacency matrix of G.

Can any one help me with a SAGE code. (Also ( kλ, λk)) should have same multiplicity

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For K=1, it is easy. But for k=2,3,4,, how to write a SAGE code. Please help.

rewi gravatar imagerewi ( 0 years ago )

See code for a similar problem at https://ask.sagemath.org/question/59220/

Max Alekseyev gravatar imageMax Alekseyev ( 0 years ago )

I tried but could not ..Can you please help me out. Where to inset that k?

rewi gravatar imagerewi ( 0 years ago )