Results 11 to 20 of about 1,255 (121)
On the isomorphism of certain primitive Q-polynomial not P-polynomial association schemes [PDF]
, 2021 In 2011, Penttila and Williford constructed an infinite new family of primitive Q-polynomial 3-class association schemes, not arising from distance regular graphs, by exploring the geometry of the lines of the unitary polar space H(3,q2), q even, with ...
Monzillo G., Siciliano A.
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Spreads in strongly regular graphs [PDF]
, 1995 A spread of a strongly regular graph is a partition of the vertex set into cliques that meet Delsarte's bound (also called Hoffman's bound). Such spreads give rise to colorings meeting Hoffman's lower bound for the chromatic number and to ...
Touchev, V.D. +9 more
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Signed graphs with at most three eigenvalues [PDF]
, 2022 summary:We investigate signed graphs with just 2 or 3 distinct eigenvalues, mostly in the context of vertex-deleted subgraphs, the join of two signed graphs or association ...
Rowlinson, Peter +2 more
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Quadrance polygons, association schemes and strongly regular graphs
, 2005 15 pages ...
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Some implications on amorphic association schemes [PDF]
, 2010 We give an overview of results on amorphic association schemes. We give the known constructions of such association schemes, and enumerate most such association schemes on up to 49 vertices. Special attention is paid to cyclotomic association schemes. We
M. Muzychuk +3 more
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Balanced colourings of strongly regular graphs
, 2005 A colouring of a strongly regular graph is an allocation of colours (or treatments) to the vertices of the graph. Such a colouring is balanced if every pair of distinct colours occurs equally often on the ends of an edge.
Bailey, Rosemary Anne, Bailey, R.A.
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Directed strongly regular graphs and divisible design graphs from Tatra association schemes
22 ...
Muzychuk, Mikhail, Ryabov, Grigory
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Some Implications on Amorphic Association Schemes
AMS classifications: 05E30, 05B20;amorphic association scheme;strongly regular graph;(negative) Latin square type;cyclotomic association scheme;strongly regular ...
Dam, E.R. van, Muzychuk, M.
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Regular graphs with four eigenvalues
We study the connected regular graphs with four distinct eigenvalues. Properties and feasibility conditions of the eigenvalues are found. Several examples, constructions and characterizations are given, as well as some uniqueness and nonexistence results.
Dam, E.R. van
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SELF-ORTHOGONAL CODES OVER A NON-UNITAL RINGFROM TWO CLASS ASSOCIATION SCHEMES
, 2023 International audienceThere is a non-unital ring I of order 4 defined by generators and relations as I = a, b | 2a = 2b = 0, a 2 = b, ab = 0. In this paper, we present special constructions of linear codes over I from the adjacency matrices of two class ...
Alahmadi, Adel +2 more
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