Results 121 to 130 of about 568,566 (214)
Chromatic polynomials with least coefficients
Discrete Mathematics, 1997 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
José Rodríguez +1 more
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Two Chromatic Polynomial Conjectures
Journal of Combinatorial Theory, Series B, 1997 Let \(P(t)\) be the chromatic polynomial of a graph. It is shown that \(P(5)^{-1}P(6)^2 P(7)^{-1}\) can be arbitrarily small, disproving a conjecture of Welsh that \(P(t)^2\geq P(t- 1)P(t+1)\), and also disproving several other conjectures of Brenti.
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Efficient Computation of Chromatic and Flow Polynomials
, 2017 This thesis surveys chromatic and flow polynomials, and presents new efficient methods to compute these polynomials on specific families of graphs. The chromatic and flow polynomials of a graph count the number of ways to color and assign flow to the ...
Brimkov, Boris
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The Astrophysical JournalThe H i 21 cm global signal from the Cosmic Dawn and the Epoch of Reionization (EoR) offers critical insights into the evolution of our Universe. Yet, its detection presents significant challenges, due to its extremely low signal-to-contamination ratio ...
Yue Wang +5 more
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In this thesis, we shall investigate chromatic polynomials of graphs, and some related polynomials. In Chapter 1, we study the chromatic polynomial written in a modified form, and use these results to characterise the chromatic polynomials of polygon ...
Wakelin, Christopher David
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Monochromatic Sums and Products of Polynomials
Discrete AnalysisMonochromatic sums and products of polynomials, Discrete Analysis 2024:5, 7 pp. An early result in Ramsey theory, Schur's theorem, states that if the positive integers are finitely coloured, then there will always be $x$ and $y$ such that $x,y$ and $x ...
Ryan Alweiss
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New expressions for order polynomials and chromatic polynomials
, 2019 Let =(,) be a simple graph with ={1,2,…,} and (,) be its chromatic polynomial. For an ordering =(1,2,…,) of elements of , let () be the number of integers , where 1≤≤−1 , with either
Dong, F. M.
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PARAMETRICAL CALCULATION TECHNIQUE OF THE NEW MIRROR PLANANASTIGMAT COMPOSITION
Весці Нацыянальнай акадэміі навук Беларусі: Серыя фізіка-тэхнічных навук, 2017 A four-mirror planaanastigmat calculation method is presented. Design feature of new mirror composition is existence of the afoсal scheme from the first two mirrors.
N. K. Artioukhina
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Maximum chromatic polynomial of 3-chromatic blocks
Discrete Mathematics, 1997 This article continues the work done by the author in [Maximum chromatic polynomials of 2-connected graphs, J. Graph Theory 18, No. 4, 329-336 (1994; Zbl 0809.05046)]. In that paper it was shown that the 2-connected graph of order \(n\) with the greatest number \(P(G,3)\) of proper 3-colourings is \(C_n\) (and, for \(n=5\), \(K_{2,3}\)), and that \(K_ ...
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Chromatic polynomials and toroidal graphs [PDF]
, 2017 The chromatic polynomials of some families of quadrangulations of the torus can be found explicitly. The method, known as ‘bracelet theory’ is based on a decomposition in terms of representations of the symmetric group.
Biggs, Norman
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