was conjectured in the 18th century. Riemann came close to proving the result, but the theory of functions of a complex variable was not sufficiently developed to enable him to complete the proof.
ay conjectured sa ika-18 siglo. Riemann dumating malapit sa proving ang resulta, ngunit ang mga teorya ng pag-andar ng isang komplikadong variable ay hindi sapat na binuo upang paganahin ang kanya upang makumpleto ang pruweba.