The simple-zero theorem for support points in Σ

Leung, Y. J.; Schober, G.

doi:10.1090/S0002-9939-1989-0948155-X

The simple-zero theorem for support points in $\Sigma$
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by Y. J. Leung and G. Schober

Proc. Amer. Math. Soc. 105 (1989), 603-608

DOI: https://doi.org/10.1090/S0002-9939-1989-0948155-X

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Abstract:

The purpose of this article is to confirm a simple-zero conjecture raised by the second author for support points in $\Sigma$. The conjecture implies that the omitted arcs of an extremal function in $\Sigma$ for a linear problem can branch out in, at most, three equiangular directions at a time.

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