Summability of Hermite expansions. II

We study the summability of n-dimensional Hermite expansions where n > 1. We prove that the critical index for the Riesz summability is (n - 1)/2. We also prove analogues of the Fejer-Lebesgue theorem and Riemann's localisation principle when the index α of the Riesz means is > (3n - 2)/6.

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