A harmonic quadrature formula characterizing open strips
1993 ◽
Vol 113
(1)
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pp. 147-151
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Keyword(s):
Let γn denote n-dimensional Lebesgue measure. It follows easily from the well-known volume mean value property of harmonic functions that if h is an integrable harmonic function on an open ball B of centre ξ0 in ℝn, where n ≥ 2, thenA converse of this result is due to Kuran [8]: if D is an open subset of ℝn such that γn(D) < + ∞ and if there exists a point ξo∈D such thatfor every integrable harmonic function h on D, then D is a ball of centre ξ0. Armitage and Goldstein [2], theorem 1, showed that the same conclusion holds under the weaker hypothesis that (1·2) holds for all positive integrable harmonic functions h on D.
Keyword(s):
2003 ◽
Vol 18
(3)
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pp. 481-484
1992 ◽
Vol 24
(6)
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pp. 559-564
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1948 ◽
Vol 44
(2)
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pp. 289-291
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Keyword(s):
1965 ◽
Vol 14
(1)
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pp. 109-111
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1949 ◽
Vol 45
(2)
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pp. 207-212
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