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Volume 21 Number 5 September 2012 Combinatorics, Probability & Computing Volume 21 Number 5 September 2012 09635483_21-5.qxd 7/14/12 1:19 PM Page 1 Volume 21 Number 5 September 2012 & Computing Combinatorics, Probability Volume 21 Number 5 September 2012 CONTENTS Are Stable Instances Easy? 643 YONATAN BILU AND NATHAN LINIAL Perfect Graphs of Fixed Density: Counting and Homogeneous Sets 661 Editor-in-Chief: Béla Bollobás JULIA BÖTTCHER, ANUSCH TARAZ AND ANDREAS WÜRFL Managing Editors: Paul Balister, Imre Leader, Strong Convergence of Partial Match Queries in Random Quadtrees 683 VOLUME 21 NUMBER 5 September 2012 643–801 PAGES Editors: Oliver Riordan NICOLAS CURIEN Noga Alon A Graph Polynomial for Independent Sets of Bipartite Graphs 695 Graham Brightwell Q . GE AND D. STEFANKOVIˇ Cˇ Jennifer T. Chayes A Generalization of the Erdos–Turán ˝ Law for the Order of Random Alan Frieze Permutation 715 Zoltán Füredi ALEXANDER GNEDIN, ALEXANDER IKSANOV AND ALEXANDER MARYNYCH Timothy Gowers Non-Three-Colourable Common Graphs Exist 734 Mark Jerrum HAMED HATAMI, JAN HLADKY´, DANIEL KRÁL’, SERGUEI NORINE AND ALEXANDER RAZBOROV Jeff Kahn Yoshiharu Kohayakawa Complexity of Ising Polynomials 743 TOMER KOTEK Alexandr Kostochka Greg Lawler Getting a Directed Hamilton Cycle Two Times Faster 773 Tomasz Luczak CHOONGBUM LEE, BENNY SUDAKOV AND DAN VILENCHIK Colin McDiarmid Brendan McKay James Oxley Yuval Peres Alexander Razborov Vojteˇch Rödl Alex Scott Vera Sós Wojciech Szpankowski Andrew Thomason Dominic Welsh Peter Winkler Cambridge Journals Online For further information about this journal please go to the journal website at: journals.cambridge.org/cpc 0963-5483 Downloaded from https://www.cambridge.org/core. IP address: 170.106.34.90, on 03 Oct 2021 at 21:55:47, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0963548312000314 09635483_21-5.qxd 7/14/12 1:19 PM Page 2 EDITOR-IN-CHIEF SUBSCRIPTIONS BÉLA BOLLOBÁS: Trinity College, Cambridge CB2 1TQ and Department of Mathematical Sciences, University of Combinatorics, Probability and Computing (ISSN: 0963-5483) is published bimonthly in 2012 in January/March (double issue), May, Memphis, Memphis, TN 38152, USA, Email: [email protected] and Email: [email protected] July, September and November by Cambridge University Press, The Edinburgh Building, Shaftesbury Road, Cambridge, CB2 8RU, MANAGING EDITORS UK / Cambridge University Press, 32 Avenue of the Americas, New York, N.Y. 10013–2473. 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