Linear relations and congruences for the coefficients of Drinfeld modular forms

We find congruences for the t-expansion coefficients of Drinfeld modular forms for \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $$GL_2 (\mathbb{F}_q [T])$$ \end{document}. We give generalized analogies of Siegel’s classical observation on SL2(ℤ) by determining all the linear relations among the initial t-expansion coefficients of Drinfeld modular forms for \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $$GL_2 (\mathbb{F}_q [T])$$ \end{document}. As a consequence spaces Mk0 are identified, in which there are congruences for the s-expansion coefficients.