08/01/16 16:53:26
P. J. Bushell and J. B. Mcleod
"Shapiro’s cyclic inequality for even n",
Journal of Inequalities and Applications Volume 7 (2002),
Issue 3, Pages 331-348
URLﾘﾝｸ(www.hindawi.com)
Abstract
In 1954 H. S. Shapiro proposed an inequality for a cyclic sum in n variables.
All the numerical evidence indicates that the inequality is true for even n≤12
and for odd n≤23. We give an analytic proof for the case n=12, which implies
the former result. The remaining case n=23 remains an open problem.