The Nielsen Coincidence Number of Maps into Tori.

Abstract

We give a formula for the Nielsen coincidence number of a
pair of maps from a surface into the 2-torus. We also show that a similar formula
gives the lower bound of the number of connected components of the coincidence
set of a pair of maps between two tori (possibly of different dimensions).
Mathematics Subject Classification (1991): 55M20
Keywords: coincidence index, coincidence Nielsen number, fixed points
and coincidences tori, Nielsen

Quaestiones Mathematicae 24(2) 2001, 217-223