A norm condition for disconjugacy of complex differential systems

Chow, Shui Nee; Wong, Pui-kei

doi:10.1090/S0002-9939-1972-0294753-6

A norm condition for disconjugacy of complex differential systems
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by Shui Nee Chow and Pui-kei Wong

Proc. Amer. Math. Soc. 34 (1972), 147-151

DOI: https://doi.org/10.1090/S0002-9939-1972-0294753-6

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Abstract:

A first order linear vector differential equation with coefficients holomorphic in the unit disk is considered. A criterion for disconjugacy expressed in terms of the Euclidean norm is given, and the condition is the best possible for this particular norm.

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