A generalized coincidence point index


  • Nasreddine Mohamed Benkafadar University of Constantine
  • M. C. Benkara-Mostefa University of Constantine




Point, Concidence point, Index, Degree, Multi-valued mapping


The paper is devoted to build for some pairs of continuous single-valued maps a coincidence point index. The class of pairs (f, g) satisfies the condition that f induces an epimorphism of the Cech homology groups with compact supports and coefficients in the field of rational numbers Q. Using this concept one defines for a class of multi-valued mappings a fixed point degree. The main theorem states that if the general coincidence point index is different from {0}, then the pair (f, g) admits at least a coincidence point. The results may be considered as a generalization of the above Eilenberg-Montgomery theorems [12], they include also, known fixed-point and coincidence-point theorems for single-valued maps and multi-valued transformations.


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Author Biographies

Nasreddine Mohamed Benkafadar, University of Constantine

Department of Mathematics, Faculty of Sciences

M. C. Benkara-Mostefa, University of Constantine

Department of Mathematics, Faculty of Sciences


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How to Cite

N. M. Benkafadar and M. C. Benkara-Mostefa, “A generalized coincidence point index”, Appl. Gen. Topol., vol. 6, no. 1, pp. 87–100, Apr. 2005.