Răspuns :
2017+2*1+2+3+......+2016:2
2017+2016+2017
2017*(2016+1)=>2017*2017
2017 la puterea a 2 => este patrat perfect
2017+2016+2017
2017*(2016+1)=>2017*2017
2017 la puterea a 2 => este patrat perfect