MathDB
Inequality in factorials

Source:

September 29, 2010
inequalitiesfactorialalgebracombinatoricscombinatorial inequalityIMO ShortlistIMO Longlist

Problem Statement

(CZS4)(CZS 4) Let K1,,KnK_1,\cdots , K_n be nonnegative integers. Prove that K1!K2!Kn![Kn]!nK_1!K_2!\cdots K_n! \ge \left[\frac{K}{n}\right]!^n, where K=K1++KnK = K_1 + \cdots + K_n