Let $l_0,c,\alpha,g$ be positive constants, and let $x(t)$ be the solution of the differential equation ([l_0\plus{}ct^{\alpha}] ^2x')'\plus{}g[l_0\plus{}ct^{\alpha}] \sin x\equal{}0, \;t \geq 0,\ \;\minus{}\frac{\pi}{2} $x(t)$ is defined on the interval $[t_0,\infty)$; furthermore, if $\alpha >2$ then for every x_0 \not\equal{} 0 there exists a $t_0$ such that $$\liminf_{t \rightarrow \infty} |x(t)| >0.$$ L. Hatvani