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A Standard Generator/Parity Check Matrix for Codes from the Cayley Tables Due to the Non-Associative (123)-Avoiding Patterns of AUNU Numbers

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A Standard Generator/Parity Check Matrix for Codes from the Cayley Tables Due to the Non-Associative (123)-Avoiding Patterns of AUNU Numbers Universal Journal of Applied Mathematics 4(2): 39-41, 2016 http://www.hrpub.org DOI: 10.13189/ujam.2016.040202 A Standard Generator/Parity Check Matrix for Codes from the Cayley Tables Due to the Non-associative (123)-Avoiding Patterns of AUNU Numbers Ibrahim A.A1, Chun P.B2,*, Abubakar S.I3, Garba A.I1, Mustafa.A1 1Department of Mathematics, Usmanu Danfodiyo University Sokoto, Nigeria 2Department of Mathematics, Plateau State University Bokkos, Nigeria 3Department of Mathematics, Sokoto State University Sokoto, Nigeria Copyright©2016 by authors, all rights reserved. Authors agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0 international License. Abstract In this paper, we aim at utilizing the Cayley Eulerian graphs due to AUNU patterns had been reported in tables demonstrated by the Authors[1] in the construction of [2] and [3]. This special class of the (132) and a Generator/Parity check Matrix in standard form for a Code (123)-avoiding class of permutation patterns which were first say C Our goal is achieved first by converting the Cayley reported [4], where some group and graph theoretic tables in [1] using Mod2 arithmetic into a Matrix with entries properties were identified, had enjoyed a wide range of from the binary field. Echelon Row operations are then applications in various areas of applied Mathematics. In[1], performed (carried out) on the matrix in line with existing we described how the non-associative and non-commutative algorithms and propositions to obtain a matrix say G whose properties of the patterns can be established using their rows spans C and a matrix say H whose rows spans , the Cayley tables where a binary operation was defined to act on dual code of C, where G and H are given as, G = (Ik| X ) and the (132) and (123)-avoiding patterns of the AUNU numbers T H= ( -X |In-k ). The report by Williem (2011) that the using a pairing scheme. adjacency Matrix of a graph can be interpreted as the In this paper, we utilize the Cayley tables generated, first generator matrix of a Code [3] is in this context extended to as matrices, then as matrices over the binary field and lastly the Cayley table which generates matrices from the transform such matrices into generator/parity check matrices permutations of points of the AUNU numbers of prime for some codes in standard cardinality. form ) . We review some basic concepts and propositions for the Keywords Carley Tables, AUNU Permutation Patterns, easy understanding of this paper. Generator Matrix, Parity Check Matrix, Standard Form, Pattern Avoidance, Echelon Row Operation, 1.1. Permutation Patterns: Non-associative, Non-commutative An arrangement of the objects 1,2,...,n is a sequence consisting of these objects arranged in any order. When in addition, a particular order is desired, such an arrangement 1. Introduction becomes an ordered permutation governed by a pattern σ and such a permutation patternσ ∈Sn naturally results In Coding theory, the generator matrix of a Code into a certain arrangement of 1,2,...,n given by plays an important role. Once the generator matrix of a code is known, such a code can easily be encoded and decoded, σσ(1) (2) . σ (n ) (1) since procedures for obtaining the parity check matrix say which is called the arrangement associated with a of the code from the generator matrix is obvious through permutation pattern σ of points of a non-empty set, existing algorithms and theorems. As such, we shall not be out of place to mention here that once we have the generator Ω={}1,2,...n (2) matrix for a particular code, then a message can be encoded, decoded and analyzed by the matrix. Given a sequence π consisting of n elements arranged The generation and analysis of some small classes of in a given pattern and another sequence σ having linear and cyclic codes from the adjacency matrices of m elements such that mn< , then σ is said to be 40 A Standard Generator/Parity Check Matrix for Codes from the Cayley Tables Due to the Non-associative (123)-Avoiding Patterns of AUNU Numbers π π contained as a pattern in provided has a subsequence 11100 which its order is isomorphic to σ . If π does not contain A = 1 0 011 σ , it is said to avoid it. The set of all σ -avoiding σ 1 1 010 permutation is denoted by Sn (). It is useful to differentiate between a subsequence and a subword. For instance, Proposition: if σπ=∈= ∈contains σ as a 4132SS48 , 78364521 11100 subword since ρ(8364)= 4132. However, The matrix A = 1 0 011 from the Cayley π =54321 ∈ S does not contain σ as a subword 5 1 1 010 although it does contain it as a subsequence. Occurrences of subwords can be overlapped. As an example, the sequence table 1 above is equivalent to a matrix σ = I 5716243∈ S7 contains two occurrences of 7162 and = G IXk knk×− , the generator matrix in standard 6234. Determination of σ has remained a hard and Sn () form of a code C spanned by the rows of A. intractable problem for a given σ containing more than Proof: suppose A above is a generator matrix for some three elements. This is among the reasons that motivate the linear code C . Then C has dimension k = 3 and length Author to construct some class of pattern-avoiding n = 5 . According to an established result, the rows of a permutations using some special subword (instead of generator matrix G are independent, which is obvious for subsequences) governed some succession scheme (Ibrahim, our G=A above. Now, since every generator matrix can 2005). Thus An (132) in this context, represents the either be put in standard form or is equivalent to a generator subwords of length n ≥ 3 that are -avoiding in A (132) n matrix in standard form ie. Ik X knk×− . Apply the being the set of strictly consecutive succession scheme following Reduced Row Echelon form (RREF) operations on containing pairs ij, such that A; i.. R23= R and ii R 323= R + R clearly gives = + ∈Ω j i1, ij . ∗ = = = us GXknk× − IXIXI k 353×− 3 32× 3 11 2. Methodology where X = X = the identity knk×− 32× 11 and Ik I3 We consider the Cayley table below, which is constructed 01 using An (132) for n = 5 as in [2] ∗ matrix of order 3. On juxtaposition of G , we obtain I Table 1. Cayley Table for n = 5 showing generated points of Ω as G= IXk knk×− which is our required result. permutations of (132) and (123)-avoiding patterns of AUNU scheme under the action of Θ . Next, we transform the A to a matrix G in standard form using the above proposition. Now, applying the Θ 1 2 3 4 5 following row operations; 1 1 3 5 2 4 11100 2 1 4 2 5 3 I = →= = and 3 1 5 4 3 2 i. R23 R on A A A 1 1 010 We now convert the entries of the Cayley table above to 1 0 011 the binary system using Modulus2 arithmetic . The table 1 1 100 thus becomes; =+I →= I II = ii. R3 R 23 R on A A A 1 1 010 Θ 1 2 3 4 5 0 1 001 1 1 1 1 0 0 II 2 1 0 0 1 1 Clearly, A can be written as 3 1 1 0 1 0 1 11 0 0 II I = = The above Cayley table is the matrix A below; A = G1 10 1 0 XIknk×− k and on 01001 Universal Journal of Applied Mathematics 4(2): 39-41, 2016 41 juxtaposition of G I , we have Acknowledgements We acknowledge the support enjoyed in this research 1 0 01 1 1 0 011 endeavour by the Institution Based Research (IBR) TETFund Grand 2015, of the Sokoto State University, G= 0 1 01 1 = IX×− = 0 1 011 k knk Sokoto, Nigeria. 0 0 101 0 0 101 which is the required generator matrix in standard form for a Code of length n = 5 and dimension 3 REFERENCES k = 3 Efficiency= Rate = and , 5 [1] Ibrahim A.A., & Abubakar S.I. (2016) Non-Associative Property of 123-Avoiding Class of Aunu Permutation and3 message digits with 2.parity check digits patterns. Advances in Pure Mathematics, 6, 51-57. ⊥ For the dual code C of the code C whose generator http://dx.doi.org/10.4236/apm.2016.62006. matrix in standard form is H (also the parity check matrix [2] Chun P.B, Ibrahim A.A, &Garba A.I, (2016) Algebraic theoretic properties of the avoiding class of AUNU IT= − of C ). We define a matrix H XInk− from permutation patterns: Application in the generation and analysis of linear codes. International Organization for Scientific Research (IOSR), Journal of Mathematics 12 (1) pp I I 1 1 01 0 G above. ie. H = and on 1-3. 1 1 10 1 [3] Chun P.B, Ibrahim A.A, &Garba A.I, (Accepted; yet to be 1 01 1 0 published) Algebraic Theoretic Properties of The juxtaposing H I , we have H = . And Non-Associative Class of (132)-Avoiding Patterns of Aunu 0 11 1 1 Permutations: Applications In The Generation And Analysis Of A General Cyclic Code. HORIZON RESEARCH we conclude that H is the parity check matrix of C and the Publishing corporation, USA. ⊥ generator matrix of the orthogonal complement of C, ( C ). [4] Ibrahim A.A &Audu M.S. (2005) some group theoretic properties of certain class of (123) and (132) – avoiding pattern of certain numbers; An enumeration scheme, African 3.
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