j-function j-invariant j-invariant The $j$-Invariant as a modular form view article J-invariant Rademacher invariant j-invariant Rademacher j-invariant [en] j-invariant invariant j-function Klein's j-invariant j-invariant j-инварианта Klein's j-invariant invariant Klein j-invariant j-function J-invariant j-invariant j invariant modular J-function j-invariant at http://en.wikipedia.org/wiki/J-invariant funzione ellittica modulare modular J-function Klein's j-invariant Klein j-invariant j-invariant English modular J-function http://en.wikipedia.org/wiki/J-invariant j-function the j-инварианта j-invariant English j-invariant j-function j-function j-function j-invariant \(j\)-invariant J-invariant the Klein j-invariant English j-invariant Klein’s -Invariant j-function j-function j-function Klein's j-invariant $j(q) = q^{-1}+\mathcal{O}(q)$