## 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

### MSC:

 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

### Keywords:

delay-logistic equation; global attractivity
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### References:

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