Language:   Search:   Contact
Zentralblatt MATH has released its new interface!
For an improved author identification, see the new author database of ZBMATH.

Query:
Fill in the form and click »Search«...
Format:
Display: entries per page entries
Zbl 1186.39010
Chatzarakis, G.E.; Philos, Ch.G.; Stavroulakis, I.P.
An oscillation criterion for linear difference equations with general delay argument.
(English)
[J] Port. Math. (N.S.) 66, No. 4, 513-533 (2009). ISSN 0032-5155; ISSN 1662-2758/e

Consider the delay difference equation $$x(n+1)-x(n)+p(n)x(\tau (n))=0,\tag*$$ where $\{p(n)\}_{n\geq 0}$ is a sequence of integers such that $\tau (n)\leq n-1$ for all $n\geq 0$ and $\lim_{n\to \infty}\tau (n)=\infty$. The authors establish the following sufficient condition for the oscillation of all solutions of ($*$): Theorem. Assume that the sequence $\{\tau (n)\}_{n\geq 0}$ is increasing, $0<\alpha \leq -1+\sqrt{2}$, where $\alpha =\lim \inf_{n\to \infty}\sum_{j=\tau (n)}^{n-1}p(j)$. If $\lim \sup_{n\to \infty}\sum_{j=\tau (n)}^{n}p(j)>1-\frac{1}{2}(1-\alpha -\sqrt{1-2\alpha -\alpha ^{2}})$, then all solutions of ($*$) are oscillatory.
[Fozi Dannan (Damascus)]
MSC 2000:
*39A21
39A06

Keywords: oscillatory solution; nonoscillatory solution; linear difference equations; delay difference equation

Highlights
Master Server