Normalizers of the Congruence Subgroups of the Hecke Groups G4 and G6 Original Research Article

Normalizers of Γ0(m)+w2 and Γ0(m)+w3 in PSL2(image) are determined. The determination of such normalizers enables us to determine the normalizers (in PSL2(image)) of the congruence subgroups G04(A) and G06(A) of the Hecke groups G4 and G6.