Results 41 to 50 of about 18,810 (231)
Equivalence classes of matrices over a finite field
International Journal of Mathematics and Mathematical Sciences, 1979 Let Fq=GF(q) denote the finite field of order q and F(m,q) the ring of m×m matrices over Fq. Let Ω be a group of permutations of Fq. If A,BϵF(m,q) then A is equivalent to B relative to Ω if there exists ϕϵΩ such that ϕ(A)=B where ϕ(A) is computed by ...
Gary L. Mullen
doaj +1 more source
Partial Steiner Triple Systems With an Almost Parallel Class Missing Any Given Point
Journal of Combinatorial Designs, EarlyView.ABSTRACT We say that a hypergraph is factor critical if it has no 1‐factor but deletion of any vertex results in a hypergraph that has a 1‐factor. We show that any factor‐critical hypergraph of order n $n$ has at least n $n$ edges, and that for all integers k > 1 $k\gt 1$ and n > 1 $n\gt 1$ with n ≡ 1 ( mod k ) $n\equiv 1({\rm{mod}}\,k)$ there exists a
Darryn Bryant +2 more
wiley +1 more source
Catalan Bounds for Symmetric Strength‐Two Orthogonal Arrays
Journal of Combinatorial Designs, EarlyView.ABSTRACT A Hamming shell construction is a two‐level array obtained by taking every binary vector of a given Hamming weight a prescribed number of times, for each weight in turn. Such arrays are invariant under all permutations of the factors, and they are strength‐two orthogonal arrays exactly when the multiplicities satisfy three linear constraints ...
Ruwan C. Karunanayaka
wiley +1 more source
A Berezin-type map and a class of weighted composition operators
Concrete Operators, 2017 In this paper we consider the map L defined on the Bergman space La2(+)$L_a^2({{\rm\mathbb{C}}_{\rm{ + }}})$ of the right half plane ℂ+ by (Lf)(w)=πM′(w)∫+(fM′)(s)|bw(s)|2dA˜(s)$(Lf)(w) = \pi M'(w)\int\limits_{{{\rm\mathbb{C}}_{\rm{ + }}}} {\left( {{f \
Das Namita
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Classifying Equidistant Permutation Codes
Journal of Combinatorial Designs, EarlyView.ABSTRACT A permutation code of length n $n$ is a set of codewords, each of which contains every symbol of a set of size n $n$ exactly once. A permutation code in which any two distinct codewords differ in the same number of coordinates is called equidistant and that number is called the distance.
Patric R. J. Östergård +1 more
wiley +1 more source
On the automorphism groups of q-enveloping algebras of nilpotent Lie algebras [PDF]
, 2006 We investigate the automorphism group of the quantised enveloping algebra U of the positive nilpotent part of certain simple complex Lie algebras g in the case where the deformation parameter q \in \mathbb{C}^* is not a root of unity. Studying its action
Launois, Stephane
core
An obstruction to the strong relative hyperbolicity of a group
, 2006 We give a simple combinatorial criterion for a group that, when satisfied, implies the group cannot be strongly relatively hyperbolic. Our criterion applies to several classes of groups, such as surface mapping class groups, Torelli groups, and ...
Javier Aramayona +5 more
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FREE GROUPS AND AUTOMORPHISM GROUPS OF INFINITE STRUCTURES
Forum of Mathematics, Sigma, 2014 Given a cardinal $\lambda $ with $\lambda =\lambda ^{\aleph _0}$
PHILIPP LÜCKE, SAHARON SHELAH
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Line Graphs of Multigraphs and the Forbidden Graph E 6
Journal of Graph Theory, EarlyView.ABSTRACT The line graph Γ of a multigraph Δ is the graph whose vertices are the edges of Δ, where two such edges are adjacent if and only if they meet in a single vertex of Δ. We provide several characterizations of such line graphs and in particular show that a graph is a line graph if and only if it does not contain one of the 32 graphs, all of which
Hans Cuypers
wiley +1 more source
Normal automorphisms of relatively hyperbolic groups
, 2010 An automorphism of a group G is normal if it fixes every normal subgroup of G setwise. We give an algebraic description of normal automorphisms of relatively hyperbolic groups.
D. Osin +3 more
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