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Annals of Mathematics, II. Series, Vol. 150, No. 3, pp. 929-975, 1999
EMIS ELibM Electronic Journals Annals of Mathematics, II. Series
Vol. 150, No. 3, pp. 929-975 (1999)

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Permanents, Pfaffian orientations, and even directed circuits

Neil Robertson, P.D. Seymour and Robin Thomas

Review from Zentralblatt MATH:

The paper deals with the following problem asked by Pólya in 1913: Given a 0-1 matrix $A$, is there a matrix $B$ obtained from $A$ by changing signs of some $1$'s to $-1$'s so that the permanent of $A$ equals the determinant of $B$? Such $B$ is called a Pólya matrix for $A$. The paper provides a structural characterization of matrices for which Pólya's matrices exist. This characterization is used to construct a polynomial-time algorithm to decide whether a matrix has its Pólya matrix.

Reviewed by M.Truszczynski

Keywords: Pfaffian orientations; permanent; determinant; Pólya matrix; characterization; polynomial-time algorithm

Classification (MSC2000): 05C75 15A15 05C85 68Q25 68R10 05C70 05C38 05B20 05C20

Full text of the article:

Electronic fulltext finalized on: 8 Sep 2001. This page was last modified: 21 Jan 2002.

© 2001 Johns Hopkins University Press
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Metadata extracted from Zentralblatt MATH with kind permission