＜正＞ It is shown in this paper that the necessary condition that a hyponormal weightedunilateral shift of norm one be unitarily equivalent to a Toeplitz operator is that theassociated weights{an}0- must stisfy 1-丨an丨~2=（1-丨a0丨~2）n+1 n≥0.As a consequence weobtain that the answer to Abrahamse’s Problem 3 is that the Bergman shift is not unitarilyequivalent to a Toeplitz operator.
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