For fundamental discriminants d=4m with class number h(−d)=8, there are exactly 29 m that are even. The three m=210,330,462 were discussed in Entry 114 since they have special properties. However, the four largest are m=598,658,742,862. Given the nome q=eπiτ, we can use the Ramanujan G and g functions 21/4Gn=q−124∏k>0(1+q2k−1)=η2(τ)η(τ2)η(2τ)21/4gn=q−124∏k>0(1−q2k−1)=η(τ2)η(τ) with τ=√−n where Ramanujan uses Gn and gn for odd n and even n, respectively. For these four m=n, then (g598)2=(η(τ2)21/4η(τ))2=(6+√26+√(6+√26)2−1)(1+√2)2(3+√132)(g658)2=(η(τ2)21/4η(τ))2=??(g762)2=(η(τ2)21/4η(τ))2=(11+√1062+√(11+√1062)2−1)(1+√2)2(7+√532)(g862)2=(η(τ2)21/4η(τ))2=?? I know the octics for the other two, though I don't know how to factor them into quartic units.
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