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1+3+5+........2017-2-4-7.........-2016=


Răspuns :

(1+2017) × 1009 : 2 - 2×(1+2+...+1008)=
= 2018×1009:2-2×1008×1009:2=
=1009×1009-1008×1009=
=1009(1009-1008)=
=1009×1=
=1009