Given the Fourier series
$$f(z) = \sum_{k=-\infty}^\infty c_k e^{ikz}$$
but with $c_k\in(\mathbb Q+ i\mathbb Q)$ instead of $\mathbb C$ (or even purely real), are the functions obtained this way in something special?
2026-04-04 21:09:00.1775336940
What functions stem from Fourier Series with rational-only coefficients?
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