Equations of the
form
| (*) |
are studied here, where p(t) ≧ 0 and uH(t,u) ≧ 0.
It is shown, among other things, that for n even all solutions of (∗) oscillate if H
is superlinear, satisfying the usual integral conditions, and u′′ + p(t)u = 0 is
nonoscillatory with p(t) “small” and decreasing. The case of n odd is also
covered and some of the recent results of Waltman, Heidel are taken as special
cases.
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