Global attractivity and oscillations in a periodic delay-logistic equation. (English) Zbl 0711.34090

The authors present two theorems for the delay-logistic equation \(\dot x(t)=r(t)x(t)[1-x(t-n\tau)/K(t)].\) One is about sufficient conditions for the global attractivity of a periodic solution when r and K are positive periodic functions of period \(\tau\) and the other about those for the oscillation of all solutions about K when K is \(\tau\)-periodic but r non- periodic. A similar problem when the time delay is not \(n\tau\) remains open.
Reviewer: Ge Weigao


34K99 Functional-differential equations (including equations with delayed, advanced or state-dependent argument)
34C10 Oscillation theory, zeros, disconjugacy and comparison theory for ordinary differential equations
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