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arXiv · 1401.1474

Identities Involving Zeros of Ramanujan and Shanks Cubic Polynomials

Stefano Barbero·Umberto Cerruti·Nadir Murru·Marco Abrate
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Abstract

In this paper we highlight the connection between Ramanujan cubic polynomials (RCPs) and a class of polynomials, the Shanks cubic polynomials (SCPs), which generate cyclic cubic fields. In this way we provide a new characterization for RCPs and we express the zeros of any RCP in explicit form, using trigonometric functions. Moreover, we observe that a cyclic transform of period three permutes these zeros. As a consequence of these results we provide many new and beautiful identities. Finally we connect RCPs to Gaussian periods, finding a new identity, and we study some integer sequences related to SCPs .

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Stefano Barbero, Umberto Cerruti, Nadir Murru, Marco Abrate. 2014-01-07. Identities Involving Zeros of Ramanujan and Shanks Cubic Polynomials. https://arxiv.org/abs/1401.1474

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