Results 41 to 50 of about 700 (120)

Fractional Chromatic Number Vs. Hall Ratio

Combinatorica
Abstract Given a graph G, its Hall ratio $$\rho (G)=\max _{H\subseteq G}\frac{|V(H)|}{\alpha (H)}$$ forms a natural lower bound for its fractional chromatic number $$\chi _f(G)$$ . A recent line of research studied the question whether $$\chi _f(G)$$
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Lower Bound on the Maximum Denominator of Fractional Chromatic Numbers

The Electronic Journal of Combinatorics
What is the least integer $\text{sd}(n)$ such that every graph on $n$ vertices has fractional chromatic number $p /q$, where $p$ and $q$ are positive integers and $q \le \text{sd}(n)$? An upper bound on the determinants of Hadamard matrices implies that $\text{sd}(n)\le 2^{-n}(n+1)^{(n+1) /2}$.
Bonamy, Marthe, Hylasová, Karolína, Kaiser, Tomáš, Sereni, Jean-Sébastien   +3 more
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Fractional Chromatic Numbers from Exact Decision Diagrams

CoRR
11 pages, 1 Figure, 1 Table, source code published at https://github.com/trewes/ddcolors, Scripts, logfiles, results and instructions for the experiments are archived at https://bonndata.uni-bonn.de/dataset.xhtml?persistentId=doi:10.60507/FK2 ...
Timo Brand, Stephan Held
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Fractional balanced chromatic number of signed subcubic graphs

Discrete Mathematics
A signed graph is a pair $(G,σ)$, where $G$ is a graph and $σ: E(G)\rightarrow \{-, +\}$, called signature, is an assignment of signs to the edges. Given a signed graph $(G,σ)$ with no negative loops, a balanced $(p,q)$-coloring of $(G,σ)$ is an assignment $f$ of $q$ colors to each vertex from a pool of $p$ colors such that each color class induces a ...
Xiaolan Hu, Luis Kuffner, Jiaao Li, Reza Naserasr, Lujia Wang, Zhouningxin Wang, Xiaowei Yu   +6 more
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Chromatic fusion: Generative multimodal neuroimaging data fusion provides multi-informed insights into schizophrenia. [PDF]

Hum Brain Mapp, 2023
Geenjaar EPT, Lewis NL, Fedorov A, Wu L, Ford JM, Preda A, Plis SM, Calhoun VD.   +7 more
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The performance of an upper bound on the fractional chromatic number of weighted graphs

Applied Mathematics Letters, 2010
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Fractional Balanced Chromatic Number and Arboricity of Planar (Signed) Graphs

Journal of Graph Theory
ABSTRACT A balanced ‐coloring of a signed graph is an assignment of colors to each vertex of from a platter of colors, such that each color class induces a balanced set (a set that does not induce a negative cycle). The fractional balanced chromatic number of , denoted , is the minimum ratio such that has a balanced ‐coloring ...
Reza Naserasr, Lan Anh Pham, Cyril Pujol, Huan Zhou   +3 more
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Polarization-independent achromatic Huygens' metalens with large numerical aperture and broad bandwidth. [PDF]

Nanophotonics, 2023
He X, Qi C, Lei S, Wong AMH.
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Visualising varnish removal for conservation of paintings by fluorescence lifetime imaging (FLIM). [PDF]

Herit Sci, 2023
Wilda CB, Burnstock A, Suhling K, Mattioli Della Rocca F, Henderson RK, Nedbal J.   +5 more
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Graph-Theoretic Limits of Distributed Computation: Entropy, Eigenvalues, and Chromatic Numbers. [PDF]

Entropy (Basel)
Deylam Salehi MR, Malak D.
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