We construct two Banach algebras, one which contains analytic semigroups $(a^z)_{Re z>0}$ such that $|a^{1+iy}| → ∞$ arbitrarily slowly as $|y| → ∞$, the other which contains ones such that $|a^{1+iy}| → ∞$ arbitrarily fast
Département de mathématiques et de statistique, Université Laval, Québec, Canada G1K 7P4
Bibliografia
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