Example image of eyePlorer eyePlorer map for 'Eisenstein series': Ferdinand Eisenstein Germany Mathematician Modular form Real analytic Eisenstein series Series (mathematics) Automorphic form Modular group Complex number Imaginary part Absolute convergence Upper half-plane Elliptic curve Theta function Weierstrass's elliptic functions Binomial coefficient Fourier series Nome (mathematics) Bernoulli number Divisor function Lambert series Riemann zeta function E8 lattice Dirichlet character Srinivasa Ramanujan Convolution Giuseppe Melfi Lie group Hilbert modular form Ring of integers Totally real number field Cusp form Henryk Iwaniec Jean-Pierre Serre Poincaré series (modular form) Almost integer Eisenstein ideal Jacobi's four-square theorem Ramanujan's congruences Selberg trace formula Weierstrass functions Parabolic induction Robert Langlands Elliptic function Steven Gaal Heegner number Genus of a multiplicative sequence Arithmetic function