Monotonicity and logarithmic convexity relating to the volume of the unit ball

نویسندگان

  • Bai-Ni Guo
  • Feng Qi
چکیده

Let Ωn stand for the volume of the unit ball in Rn for n ∈ N. In the present paper, we prove that the sequence Ω 1/(n lnn) n is logarithmically convex and that the sequence Ω 1/(n lnn) n Ω 1/[(n+1) ln(n+1)] n+1 is strictly decreasing for n ≥ 2. In addition, some monotonic and concave properties of several functions relating to Ωn are extended and generalized.

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عنوان ژورنال:
  • Optimization Letters

دوره 7  شماره 

صفحات  -

تاریخ انتشار 2013