## On a simple quartic family of Thue equations over imaginary quadratic number fields

### Volume 208 / 2023

Acta Arithmetica 208 (2023), 355-389
MSC: Primary 11D59; Secondary 11R11, 11Y50.
DOI: 10.4064/aa230329-19-6
Published online: 8 September 2023

#### Abstract

Let $t$ be any imaginary quadratic integer with $|t|\geq 100$. We prove that the inequality \[ |F_t(X,Y)| = | X^4 - t X^3 Y - 6 X^2 Y^2 + t X Y^3 + Y^4 | \leq 1 \] has only trivial solutions $(x,y)$ in integers of the same imaginary quadratic number field as $t$. Moreover, we prove results on the inequalities $|F_t(X,Y)| \leq C|t|$ and $|F_t(X,Y)| \leq |t|^{2 -\epsilon }$. These results follow from an approximation result that is based on the hypergeometric method. The proofs in this paper require a fair amount of computations, for which the code (in Sage) is provided.