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Limit circle/limit point criteria for second-order sublinear differential equations with damping term. (English) Zbl 1272.34034
Consider the scalar equation $$(a(t)y')'+ b(t)y'+ r(t) y^\gamma= 0,\tag{*}$$ where $a,r: \Bbb R_+\to \Bbb R$ are sufficiently smooth, $b: \Bbb R_+\to\Bbb R_+$ is continuous, $\gamma= 2k-1$ with $k= (M+ N- 1)/(2N- 1)$, where $M$ and $N$ are positive integers. The authors present necessary and sufficient conditions for $(*)$ to be of limit-circle type or limit-point type.

##### MSC:
 34B20 Weyl theory and its generalizations
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##### References:
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