IMO Shortlist 1982 problem 11
Dodao/la:
arhiva2. travnja 2012. (a) Find the rearrangement
of
that maximizes
(b) Find the rearrangement that minimizes
%V0
(a) Find the rearrangement $\{a_1, \dots , a_n\}$ of $\{1, 2, \dots, n\}$ that maximizes
$$a_1a_2 + a_2a_3 + \cdots + a_na_1 = Q.$$
(b) Find the rearrangement that minimizes $Q.$
Izvor: Međunarodna matematička olimpijada, shortlist 1982
Školjka 
