Abstract
Let P,Q, and R denote the Ramanujan Eisenstein series. We compute algebraic relations in terms of P(q i) (i=1,2,3,4), Q(q i) (i=1,2,3), and R(q i) (i=1,2,3). For complex algebraic numbers q with 0<|q|<1 we prove the algebraic independence over ℚ of any three-element subset of {P(q),P(q 2),P(q 3),P(q 4)} and of any two-element subset of {Q(q),Q(q 2),Q(q 3)} and {R(q),R(q 2),R(q 3)}, respectively. For all the results we use some expressions of \(P(q^{i_{1}}), Q(q^{i_{2}}) \), and \(R(q^{i_{3}}) \) in terms of theta constants. Computer-assisted computations of functional determinants and resultants are essential parts of our proofs.
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Elsner, C., Shiokawa, I. On algebraic relations for Ramanujan’s functions. Ramanujan J 29, 273–294 (2012). https://doi.org/10.1007/s11139-012-9384-8
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DOI: https://doi.org/10.1007/s11139-012-9384-8