Báo cáo toán hoc:" An Elementary Chromatic Reduction for Gain Graphs and Special Hyperplane" pps

Báo cáo toán hoc:" An Elementary Chromatic Reduction for Gain Graphs and Special Hyperplane" pps

Báo cáo toán hoc:" An Elementary Chromatic Reduction for Gain Graphs and Special Hyperplane" pps

... balanced, and we define the chromatic and zero-free chromatic polynomials by means of (5.3) and (5.4). Proposition 5.4. The total chromatic polynomial is a weak chromatic invariant of gain graphs. ... Cat alan, Shi, and Linial graphs satisfy the hypotheses of Corollary 10.4 and the graphs between Catalan and Shi are co mplete, it is a routine matter to evaluate their...
Ngày tải lên : 08/08/2014, 01:20
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Báo cáo toán học: "An elementary proof of the hook formula" ppt

Báo cáo toán học: "An elementary proof of the hook formula" ppt

... present here an elementary new proof which uses nothing more than the fundamental theorem of algebra. This proof was suggested by a q, t-analog of the hook formula given by Garsia and Tesler, and is ... the proof given here. Thanks also is due to the National Science Foundation for support, and to an anonymous reviewer for many useful suggestions. 3 A proof of the hook formula...
Ngày tải lên : 07/08/2014, 15:23
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Báo cáo toán học: "An improved tableau criterion for Bruhat order" ppt

Báo cáo toán học: "An improved tableau criterion for Bruhat order" ppt

... <x r (for if x i,k >x k then x i−1,k−1 = x i,k and hence y i−1,k−1 ≤ y i,k <x i,k = x i−1,k−1 which contradicts An improved tableau criterion for Bruhat order Anders Bj ¨ orner and Francesco ... Proctor [P] and for certain affine Weyl groups by Bj¨orner and Brenti [BB] and by Eriksson and Eriksson [HE, EE]. In 1977 Deodhar [D] published a characterization of Bruhat...
Ngày tải lên : 07/08/2014, 06:20
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Báo cáo toán học: " AN EXACT PERFORMANCE BOUND FOR AN O(m + n) TIME GREEDY MATCHING PROCEDURE" pptx

Báo cáo toán học: " AN EXACT PERFORMANCE BOUND FOR AN O(m + n) TIME GREEDY MATCHING PROCEDURE" pptx

... of method (perhaps the greedy procedure) for handling dense graphs, and another kind of method (perhaps an augmenting path algorithm) for handling other graphs. It may be interesting to investigate ... increasing on [2,n], since f(r) and g(r) are. Also, b(n, r) = max(f(n, r),g(n, r)) when n ≥ 2 and r ≥ 1. (7) 4 Performance Guarantees The following performance guarantee for the...
Ngày tải lên : 07/08/2014, 06:20
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Báo cáo toán học: " On the chromatic number of intersection graphs of convex sets in the plane" ppt

Báo cáo toán học: " On the chromatic number of intersection graphs of convex sets in the plane" ppt

... A+u  (respectively, V  = A + v  ). Since U  and V  are between A and B, by Lemma 4, U  and V  intersect V and each other. Let u  be the point on L u with the y-coordinate equal to y v and U  = A + u  .SinceU  intersects ... if and only if they have common elements. Asplund and Gr¨unbaum [3] and Gy´arf´as and Lehel [11, 9] started studying many interesting probl...
Ngày tải lên : 07/08/2014, 08:20
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Báo cáo toán học: "An Ehrhart Series Formula For Reflexive Polytopes" pptx

Báo cáo toán học: "An Ehrhart Series Formula For Reflexive Polytopes" pptx

... 1] and hence we get our result. This behavior can be generalized as follows: Corollary 1 Suppose that P and Q are as in Theorem 1 and that {H i } k i=1 and {K j } l j=1 are halfspaces of the form ... Dual polyhedra and mirror symmetry for Calabi-Yau hypersurfaces in toric varieties. J. Algebraic Geom., 3(3):493–535, 1994. [2] Matthias Beck and Serkan Ho¸sten. Cyclotomic polytope...
Ngày tải lên : 07/08/2014, 13:21
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Báo cáo toán học: "On the chromatic number of simple triangle-free triple systems" pps

Báo cáo toán học: "On the chromatic number of simple triangle-free triple systems" pps

... t u = t v = t then c ∈ L (t) (w) and so κ(w) = c. If t u < t v = t then vw is an edge of G (t) and κ(vw) = c and so c ∈ L (t) (w) and again κ(w) = c. 6 Parameters for the problem We will now ... (17) Fix u and condition on the values γ w (c), η w (c) for all c ∈ C and all w /∈ N(u) and for w = u. Now write u ∼ v to mean that there exists w such that uvw is an edge...
Ngày tải lên : 07/08/2014, 21:20
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Báo cáo toán hoc:" An Edge-Minimization Problem for Regular Polygons " pps

Báo cáo toán hoc:" An Edge-Minimization Problem for Regular Polygons " pps

... v} and c 1 = c 2 such that f 1 − c 1 g 1 = f j 0 − c 1 g j 0 and f 1 − c 2 g 1 = f j 0 − c 2 g j 0 . Thus f j 0 = f 1 and g j 0 = g 1 , and (16) becomes (after swapping the indexes u + 1 and ... product A(x)(1 + x p k + · · · + x (p−1)p k ) is expanded and collected with respect to x is ap, where a is the number of terms in the expanded and collected form of A(x). Since these e...
Ngày tải lên : 08/08/2014, 01:20
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Báo cáo toán học: "An Extremal Property of Tur´n Graphs a" potx

Báo cáo toán học: "An Extremal Property of Tur´n Graphs a" potx

... = P T 3 (6) (4) = 96, and so this ends the proof of Case 2, and of Theorem 1.  Acknowledgment The authors are thankful to Sebastian Cioab˘a, Gary Ebert, and Qing Xiang for their comments on ... [10], Read and Tutte [11], Read and Royle [12], and recent preprints by Norine [9] and Zhao [16]. Let F n,m consist o f all (n, m) -graphs, that is, graphs of order n and size m. T...
Ngày tải lên : 08/08/2014, 12:23
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