User David Roberson

10 votes

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Computer program for counting graph homomorphisms

answered Jun 20, 2018 at 20:01

9 votes

Spectrum of orthogonality graph (2)

answered Mar 9, 2018 at 14:19

9 votes

Finite sets of vectors closed under an orthogonality property

answered Oct 23, 2015 at 18:56

8 votes

Graph homomorphisms and line graph

answered Oct 15, 2015 at 4:10

7 votes

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Projective graphs

answered Feb 1, 2019 at 11:32

6 votes

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Does the clique-coclique bound hold for all walk-regular graphs?

answered Jan 3, 2018 at 13:30

5 votes

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Infinite graph with lots of non-isomorphic induced subgraphs

answered Jul 16, 2018 at 14:12

5 votes

The chromatic number of a Hamming-related graph

answered Sep 1, 2016 at 13:39

5 votes

A graph spectra problem?

answered Sep 6, 2016 at 20:57

4 votes

How do eigenvalues of combinatorial Laplacian relates to automorphisms in graphs?

answered May 1, 2018 at 12:03

4 votes

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Infinite connected $k$-regular graphs

answered Jul 7, 2018 at 18:03

4 votes

Vector chromatic number and Lovasz theta

answered Mar 11, 2013 at 4:09

4 votes

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Contracting non-adjacent points in the icosahedron

answered Mar 18, 2019 at 13:52

4 votes

Does there exist a nontrivial perfect group with a "locally commuting" presentation?

answered Jan 15 at 10:35

3 votes

Do graphs with $\omega(G) = \chi(G)$ grow "common" as $|V|$ grows large?

answered Nov 23, 2015 at 11:40

3 votes

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Commutative graph product with multiplicative independence number?

answered Apr 25, 2017 at 19:26

3 votes

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Product of critical graphs and Hedetniemi's conjecture

answered May 12, 2017 at 12:03

2 votes

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Critical graphs and endomorphisms

answered Aug 31, 2016 at 12:35

2 votes

If two vertices induce isomorphic subgraphs when they are removed, are they conjugate?

answered Mar 5 at 20:21

2 votes

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Homomorphisms relationship with Graph Degeneracy

answered Mar 7 at 22:06

2 votes

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Co-spectral fractional isomorphic graphs with different Laplacian spectrum

answered Jun 21, 2019 at 21:41

2 votes

The bipartite double of two regular graphs

answered Jan 25, 2023 at 15:25

1 vote

Positive-semidefiniteness of Laplacian of signed graph

answered Jul 5 at 10:19

1 vote

SDP relaxation vs LP relaxation

answered Sep 6, 2016 at 17:31

1 vote

Triange-free graph and its complement has Lovász number > 3

answered Jun 29, 2016 at 14:26

1 vote

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Largest edge set compatible with graph endomorphisms

answered Sep 22, 2017 at 14:23

0 votes

ILP for minimum edge coloring problem

answered Oct 16, 2015 at 10:51

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27 Answers

Computer program for counting graph homomorphisms

Spectrum of orthogonality graph (2)

Finite sets of vectors closed under an orthogonality property

Graph homomorphisms and line graph

Projective graphs

Does the clique-coclique bound hold for all walk-regular graphs?

Infinite graph with lots of non-isomorphic induced subgraphs

The chromatic number of a Hamming-related graph

A graph spectra problem?

How do eigenvalues of combinatorial Laplacian relates to automorphisms in graphs?

Infinite connected $k$-regular graphs

Vector chromatic number and Lovasz theta

Contracting non-adjacent points in the icosahedron

Does there exist a nontrivial perfect group with a "locally commuting" presentation?

Do graphs with $\omega(G) = \chi(G)$ grow "common" as $|V|$ grows large?

Commutative graph product with multiplicative independence number?

Product of critical graphs and Hedetniemi's conjecture

Critical graphs and endomorphisms

If two vertices induce isomorphic subgraphs when they are removed, are they conjugate?

Homomorphisms relationship with Graph Degeneracy

Co-spectral fractional isomorphic graphs with different Laplacian spectrum

The bipartite double of two regular graphs

Positive-semidefiniteness of Laplacian of signed graph

SDP relaxation vs LP relaxation

Triange-free graph and its complement has Lovász number > 3

Largest edge set compatible with graph endomorphisms

ILP for minimum edge coloring problem