Răspuns:
6059145
Explicație pas cu pas:
f(0)=0+1
f(1) =3*1+1
f(2) =3*2+1
.......................
f(2009)=3*2009+1
f(0)+f(1)+....+f(2009)=3(1+2+...+2009) +1+1+.+1 (2010 de 1)=
3*2009*2010/2+2010=6057135+2010=6059145
altfel
1+4+7+...+6028=6029*((6028-1)/3+1)=6029*2010/2=6059145
