RT Journal Article T1 Mayer-vietoris property of the fixed point index A1 Barge, Héctor A1 Wójcik, K. AB In this paper we study a Mayer-Vietoris kind of formula for the fixed point index of maps of ENR triplets f : (X;X1,X2) → (X;X1,X2) having compact fixed point set. We prove it under some suitable conditions. For instance when (X;X1,X2) = (En;En+,En −). We use these results to generalize Poincar´e-Bendixson index formula for vector fields to continuos maps having a sectorial decomposition, to study the fixed point index i(f, 0) of orientation preserving homeomorphisms of E2 + and (E3;E3 +,E3 −) and the fixed point index in the invariant subspace. PB Juliusz Schauder Center SN 1230-3429 YR 2017 FD 2017 LK https://hdl.handle.net/20.500.14352/18493 UL https://hdl.handle.net/20.500.14352/18493 LA eng NO Ministerio de Economía y Competitividad (MINECO) NO Faculty of Mathematics and Computer Science of Jagiellonian University in Krakow DS Docta Complutense RD 6 abr 2025