MathDB
Number Theory problem

Source: EGMO 2018 Moldova TST

February 11, 2018
number theory

Problem Statement

Find all sets of positive integers A={a1,a2,...a19}A=\big\{ a_1,a_2,...a_{19}\big\} which satisfy the following: 1)a1+a2+...+a19=2017;1\big) a_1+a_2+...+a_{19}=2017; 2)S(a1)=S(a2)=...=S(a19)2\big) S(a_1)=S(a_2)=...=S(a_{19}) where S(n)S\big(n\big) denotes digit sum of number nn.