文摘
We prove the modularity of the level 13 analogue f463cfea9707be" title="Click to view the MathML source">r13(τ) of the Rogers–Ramanujan continued fraction. We establish some properties of f463cfea9707be" title="Click to view the MathML source">r13(τ) using the modular function theory. We first prove that f463cfea9707be" title="Click to view the MathML source">r13(τ) is a generator of the function field on Γ0(13). We then find modular equations of f463cfea9707be" title="Click to view the MathML source">r13(τ) of level n for every positive integer n by using affine models of modular curves; this is an extension of Cooper and Ye's results with levels n=2,3 and 7 to every level n . We further show that the value f463cfea9707be" title="Click to view the MathML source">r13(τ) is an algebraic unit for any τ∈K−Q, where K is an imaginary quadratic field.