MathDB
Another year-based olympiad problem

Source: 2016 BAMO-12 #4

February 25, 2016
algebraProofOlympiad

Problem Statement

Find a positive integer NN and a1,a2,,aNa_1, a_2, \cdots, a_N where ak=1a_k = 1 or ak=1a_k = -1, for each k=1,2,,N,k=1,2,\cdots,N, such that a113+a223+a333+aNN3=20162016a_1 \cdot 1^3 + a_2 \cdot 2^3 + a_3 \cdot 3^3 \cdots + a_N \cdot N^3 = 20162016 or show that this is impossible.