A = 2017 + 2*(1+2+3+...+2016)
Dar 1+2+3+...+2016 = (1+2016)*2016/2 = 2017*1008
Atunci A = 2017 + 2*2017*1008 = 2017(1 + 2*1008) = 2017(1 + 2016) = 2017*2017 = 2017^2
A:2017 = 2017^2 : 2017 = 2017
A = 2017 + 2*[(2016*2017)/2]
am aplicat suma lui gauss
A = 2017 + 2*(1008*2017)
A = 2017 + 2* 2 033 136
A = 2017 + 4 066 272
A = 4 068 289
4 068 289 : 2017 = 2017
