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arXiv · 1801.04392

Certain quaternary quadratic forms of level 48 and their representation numbers

B. Ramakrishnan·Brundaban Sahu·Anup Kumar Singh
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Abstract

In this paper, we find a basis for the space of modular forms of weight $2$ on $\Gamma_1(48)$. We use this basis to find formulas for the number of representations of a positive integer $n$ by certain quaternary quadratic forms of the form $\sum_{i=1}^4 a_i x_i^2$, $\sum_{i=1}^2 b_i(x_{2i-1}^2 + x_{2i-1}x_{2i}+x_{2i}^2)$ and $a_1x_1^2 + a_2 x_2^2 + b_1(x_3^2+x_3x_4+x_4^2)$, where $a_i$'s belong to $\{1,2,3,4,6,12\}$ and $b_i$'s belong to $\{1,2,4,8,16\}$.

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B. Ramakrishnan, Brundaban Sahu, Anup Kumar Singh. 2018-01-13. Certain quaternary quadratic forms of level 48 and their representation numbers. https://arxiv.org/abs/1801.04392

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