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作者单位:Maru Guadie (1) Eugenia Malinnikova (1)
1. Department of Mathematical Sciences, Norwegian University of Science and Technology, 7491聽, Trondheim, Norway
ISSN:2195-3724
文摘
We give an elementary argument to prove the Three Balls Theorem for continuous harmonic functions in \({\mathbb {R}}^n\) which can be adapted to the case of discrete harmonic functions on the lattice. The discrete analog of the Three Balls Theorem that we obtain contains an additional term that depends on the mesh size of the lattice and goes to zero when the mesh size goes to zero. We also show that any discrete harmonic function on a cube coincides with a discrete harmonic polynomial on this cube.