365 search results - page 30 / 73 » On the combinatorics of Galois numbers |
103
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COMBINATORICS
2006
14 years 12 months ago
2006
A proper edge colouring of a graph is neighbour-distinguishing if for all pairs of adjacent vertices v, w the set of colours appearing on the edges incident with v is not equal to...
COMBINATORICS
2006
14 years 12 months ago
2006
A graph is Y Y reducible if it can be reduced to isolated vertices by a sequence of series-parallel reductions and Y Y transformations. It is still an open problem to characterize...
COMBINATORICS
2006
14 years 12 months ago
2006
We prove that n+h 4 vertex guards are always sufficient to see the entire interior of an n-vertex orthogonal polygon P with an arbitrary number h of holes provided that there exis...
125
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COMBINATORICS
2006
14 years 12 months ago
2006
We present an algorithm for finding a system of recurrence relations for the number of permutations of length n that satisfy a certain set of conditions. A rewriting of these rela...
COMBINATORICS
2007
14 years 11 months ago
2007
Let k3(n) denote the minimal cardinality of a ternary code of length n and covering radius one. In this paper we show k3(7) ≥ 156 and k3(8) ≥ 402 improving on the best previou...