منابع مشابه
Finite groups have even more centralizers
For a finite group $G$, let $Cent(G)$ denote the set of centralizers of single elements of $G$. In this note we prove that if $|G|leq frac{3}{2}|Cent(G)|$ and $G$ is 2-nilpotent, then $Gcong S_3, D_{10}$ or $S_3times S_3$. This result gives a partial and positive answer to a conjecture raised by A. R. Ashrafi [On finite groups with a given number of centralizers, Algebra Collo...
متن کاملMaking Even Swaps Even Easier
This paper introduces an approach to support different phases of the Even Swaps process by Preference Programming, which is a framework for modeling incomplete information within multiattribute value theory. In the approach, the Even Swaps process is carried out as usual, but in parallel the preferences of the decision maker are modeled with a Preference Programming model, which is also updated...
متن کاملFinding Even Cycles Even Faster
We describe efficient algorithms for finding even cycles in undirected graphs. Our main results are the following: (i) For every k ≥ 2, there is an O(V ) time algorithm that decides whether an undirected graph G = (V,E) contains a simple cycle of length 2k and finds one if it does. (ii) There is an O(V ) time algorithm that finds a shortest even cycle in an undirected graph G = (V,E).
متن کاملFinding Even Subgraphs Even Faster
Problems of the following kind have been the focus of much recent research in the realm of parameterized complexity: Given an input graph (digraph) on n vertices and a positive integer parameter k, find if there exist k edges (arcs) whose deletion results in a graph that satisfies some specified parity constraints. In particular, when the objective is to obtain a connected graph in which all th...
متن کاملOn Even and Harmonic-Even Partial Cubes
Fukuda and Handa [7] asked whether every even partial cube G is harmonic-even. It is shown that the answer is positive if the isometric dimension of G equals its diameter which is in turn true for partial cubes with isometric dimension at most 6. Under an additional technical condition it is proved that an even partial cube G is harmonic-even or has two adjacent vertices whose diametrical verti...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Iowa Review
سال: 1973
ISSN: 0021-065X,2330-0361
DOI: 10.17077/0021-065x.1585