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Green’s functions and comparison theorems for differential equations on measure chains. (English) Zbl 0938.34027

Summary: The authors are concerned with the selfadjoint equation

Lx(t)=[r(t)x Δ (t)] Δ +q(t)x(σ(t))=0·

They study certain Green functions associated with this equation. Comparison theorems for initial value problems and boundary value problems are given.

MSC:
34C10Qualitative theory of oscillations of ODE: zeros, disconjugacy and comparison theory
34B27Green functions
34A12Initial value problems for ODE, existence, uniqueness, etc. of solutions