Abstract
Using Hecke characters, we construct two infinite families of newforms with complex multiplication, one by \({\mathbb {Q}}(\sqrt{-3})\) and the other by \({\mathbb {Q}}(\sqrt{-2})\). The values of the p-th Fourier coefficients of all the forms in each family can be described by a single formula, which we provide explicitly. This allows us to establish a formula relating the p-th Fourier coefficients of forms of different weights, within each family. We then prove congruence relations between the p-th Fourier coefficients of these newforms at all odd weights and values coming from two of Zagier’s sporadic Apéry-like sequences.
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The second author is supported by a grant from the Simons Foundation (353329, Dermot McCarthy).
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Gomez, A., McCarthy, D. & Young, D. Apéry-like numbers and families of newforms with complex multiplication. Res. number theory 5, 5 (2019). https://doi.org/10.1007/s40993-018-0145-7
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DOI: https://doi.org/10.1007/s40993-018-0145-7