Ramanujan series for Epstein zeta functions

In the spirit of Ramanujan, we derive exponentially fast convergent series for Epstein zeta functions (E^{varGamma _0(N)}(z,s)) on the Hecke congruence groups ( varGamma _0(N),Nin mathbb {Z}_{>0}), where z is an arbitrary point in the upper half-plane ( mathfrak {H}) and (sin mathbb {Z}_{>1}). These Ramanujan series can be reformulated as integrations of modular forms, in the framework of Eichler integrals. Particular cases of these Eichler integrals recover part of the recent results reported by Wan and Zucker (arXiv:1410.7081v1, 2014).