Derivatives of entire functions and a question of Pólya. II
Derivatives of entire functions and a question of Pólya. II
It is shown that if <italic>f</italic> is an entire function of infinite order, which is real on the real axis and has, along with <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="f prime"> <mml:semantics> <mml:msup> <mml:mi>f</mml:mi> <mml:mo>′</mml:mo> </mml:msup> <mml:annotation encoding="application/x-tex">f’</mml:annotation> </mml:semantics> </mml:math> </inline-formula>, only real zeros, then <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="f"> <mml:semantics> …