Results 31 to 40 of about 141,047 (269)
Generating trees for partitions and permutations with no k-nestings [PDF]
Discrete Mathematics & Theoretical Computer Science, 2012 We describe a generating tree approach to the enumeration and exhaustive generation of k-nonnesting set partitions and permutations. Unlike previous work in the literature using the connections of these objects to Young tableaux and restricted lattice ...
Sophie Burrill +3 more
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J. Integer Seq., 2015 Define a sequence of positive integers by the rule that a(n) = n for 1 <= n <= 3, and for n >= 4, a(n) is the smallest number not already in the sequence which has a common factor with a(n-2) and is relatively prime to a(n-1). We show that this is a permutation of the positive integers. The remarkable graph of this sequence consists of runs of
David L. Applegate +5 more
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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
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Permutations by Interchanges [PDF]
The Computer Journal, 1963 Methods for obtaining all possible permutations of a number of objects, in which each permutation differs from its predecessor only by the interchange of two of the objects, are discussed. Details of two programs which produce these permutations are given, one allowing a specified position to be filled by each of the objects in a predetermined order ...
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Image Encryption Algorithm Based on Substitution Principle and Shuffling Scheme [PDF]
Engineering and Technology Journal, 2020 This research presents a method of image encryption that has been designed based on the algorithm of complete shuffling, transformation of substitution box, and predicated image crypto-system. This proposed algorithm presents extra confusion in the first
Atyaf Hamad, Alaa Farhan
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Profiles of Permutations [PDF]
The Electronic Journal of Combinatorics, 2009 This paper develops an analogy between the cycle structure of, on the one hand, random permutations with cycle lengths restricted to lie in an infinite set $S$ with asymptotic density $\sigma$ and, on the other hand, permutations selected according to the Ewens distribution with parameter $\sigma$.
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Estimating significances of differences between slopes: A new methodology and software [PDF]
Computational Ecology and Software, 2013 Determining the significance of slope differences is a common requirement in studies of self-thinning, ontogeny and sexual dimorphism, among others. This has long been carried out testing for the overlap of the bootstrapped 95% confidence intervals of ...
Vasco M. N. C. S. Vieira, Joel Creed
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Entropy, 2019 Image encryption is one of the essential tasks in image security. In this paper, we propose a novel approach that integrates a hyperchaotic system, pixel-level Dynamic Filtering, DNA computing, and operations on 3D Latin Cubes, namely DFDLC, for image ...
Taiyong Li +4 more
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Permutation Statistics of Indexed Permutations
European Journal of Combinatorics, 1994 The definitions of descent, exceedance, major index, inversion index and Denert's statistic for the elements of the symmetric group \({\mathcal S}_ d\) are generalized to indexed permutations, i.e. the elements of the group \(S^ n_ d:=\mathbb{Z}_ n\wr{\mathcal S}_ d\), where \(\wr\) is the wreath product with respect to usual action of \({\mathcal S}_ ...
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Permutation Reconstruction [PDF]
The Electronic Journal of Combinatorics, 2006 In this paper, we consider the problem of permutation reconstruction. This problem is an analogue of graph reconstruction, a famous question in graph theory. In the case of permutations, the problem can be stated as follows: In all possible ways, delete $k$ entries of the permutation $p=p_1p_2p_3...p_n$ and renumber accordingly, creating $n \choose k$
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