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Articles de revista [43]
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The conjugacy problem for freebycyclic groups
(200404)
External research report
Open AccessWe show that the conjugacy problem is solvable in [finitely generated free]bycyclic groups, by using a result of O. Maslakova that one can algorithmically find generating sets for the fixed sub groups of free group ... 
The automorphism group of a freebycyclic group in rank 2
(200705)
Article
Open AccessLet ¡ be an automorphism of a free group F 2 of rank 2 and let M ¡ = F 2 o ¡ Z be the corresponding mapping torus of ¡ . We prove that the group Out ( M ¡ ) is usually virtually cyclic. More over, ... 
Absolutetype shaft encoding using LFSR sequences with a prescribed length
(20080331)
Article
Open AccessMaximallength binary sequences have existed for a long time. They have many interesting properties, and one of them is that, when taken in blocks of n consecutive positions, they form 2n  1 different codes in a closed ... 
Absolute type shaft encoding using LFSR sequences with prescribed length
(200602)
Article
Open AccessMaximallength binary sequences have been known for a long time. They have many interesting properties, one of them is that when taken in blocks of n consecutive positions they form 2 n ° 1 diÆerent codes in a ... 
Completion and decomposition of a clutter into representable matroids
(Elsevier, 20150501)
Article
Restricted access  publisher's policyThis paper deals with the question of completing a monotone increasing family of subsets Gamma of a finite set Omega to obtain the linearly dependent subsets of a family of vectors of a vector space. Specifically, we prove ... 
Fixed subgroups are compressed in surface groups
(20150801)
Article
Restricted access  publisher's policyFor a compact surface Sigma (orientable or not, and with boundary or not), we show that the fixed subgroup, Fix B, of any family B of endomorphisms of pi(1)(Sigma) is compressed in pi(1)(Sigma), i.e. rk(Fix B) <= rk(H) for ... 
Extensions and presentations of transversal matroids
(20151102)
Article
Restricted access  publisher's policyA transversal matroid MM can be represented by a collection of sets, called a presentation of MM, whose partial transversals are the independent sets of MM. Minimal presentations are those for which removing any element ... 
On the diameter of random planar graphs
(2015)
Article
Open AccessWe show that the diameter diam(Gn) of a random labelled connected planar graph with n vertices is equal to n1/4+o(1) , in probability. More precisely, there exists a constant c > 0 such that {equation presented} for ˜ small ... 
Grouptheoretic orbit decidability
(De Gruytr, 20141201)
Article
Open AccessA recent collection of papers in the last years have given a renovated interest to the notion of orbit decidability. This is a new quite general algorithmic notion, connecting with several classical results, and closely ... 
An involution on bicubic maps and beta(0,1)trees
(2015)
Article
Open AccessBicubic maps are in bijection with (0 ; 1)trees. We introduce two new ways of decomposing (0 ; 1)trees. Using this we de ne an endofunc tion on (0 ; 1)trees, and thus also on bicubic maps. We show that ...