MathDB
(a_1+a_2+...+a_m)/m >= \sqrt{(a_1^2+a_2^2+...+a_{2014}^2)/2014} , max m

Source: INAMO Shortlist 2014 A5

May 21, 2019
algebrainequalities

Problem Statement

Determine the largest natural number mm such that for each non negative real numbers a1a2...a20140a_1 \ge a_2 \ge ... \ge a_{2014} \ge 0 , it is true that a1+a2+...+amma12+a22+...+a201422014\frac{a_1+a_2+...+a_m}{m}\ge \sqrt{\frac{a_1^2+a_2^2+...+a_{2014}^2}{2014}}