## Functiones et Approximatio Commentarii Mathematici

### Theta products and eta quotients of level $24$ and weight $2$

#### Abstract

We find bases for the spaces $M_2\Big(\Gamma_0(24),(\frac{d}{\cdot})\Big)$ ($d=1,8,12, 24$) of modular forms. We determine the Fourier coefficients of all $35$ theta products $\varphi[a_1,a_2,a_3,a_4](z)$ in these spaces. We then deduce formulas for the number of representations of a positive integer $n$ by diagonal quaternary quadratic forms with coefficients $1$, $2$, $3$ or $6$ in a uniform manner, of which $14$ are Ramanujan's universal quaternary quadratic forms. We also find all the eta quotients in the Eisenstein spaces $E_2\Big(\Gamma_0(24),(\frac{d}{\cdot})\Big)$ ($d=1,8,12, 24$) and give their Fourier coefficients.

#### Article information

Source
Funct. Approx. Comment. Math., Volume 57, Number 2 (2017), 205-234.

Dates
First available in Project Euclid: 28 March 2017

https://projecteuclid.org/euclid.facm/1490688025

Digital Object Identifier
doi:10.7169/facm/1628

Mathematical Reviews number (MathSciNet)
MR3732896

Zentralblatt MATH identifier
06864172

#### Citation

Alaca, Ayşe; Alaca, Şaban; Aygin, Zafer Selcuk. Theta products and eta quotients of level $24$ and weight $2$. Funct. Approx. Comment. Math. 57 (2017), no. 2, 205--234. doi:10.7169/facm/1628. https://projecteuclid.org/euclid.facm/1490688025

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