c:=300    (*   c is actually going to Infinity  *)
a:=3.67

fonk1:=(Zeta[a])^2 - Zeta[2*a]
fonk2:=2*Sum[Sum[1/(((k-r)^a)*(k^a)) , {r,1,k-1}] , {k,1,c}]

N[fonk1,10]
N[fonk2,10]

0.2235594415
0.2235592403

    Source: geocities.com/timeparadox