A Class of Trinomials with Galois Group Sn
Abstract
A well known result of Schur states that if n is a positive integer and a0, a1,…,an are arbitrary integers with a0an coprime to n!, then the polynomial is irreducible over the field ℚ of rational numbers. In case each ai = 1, it is known that the Galois group of fn(x) over ℚ contains An, the alternating group on n letters. In this paper, we extend this result to a larger class of polynomials fn(x) which leads to the construction of trinomials of degree n for each n with Galois group Sn, the symmetric group on n letters.
The financial support by CSIR (grant 09/135(0539)/2008-EMR-I) and National Board for Higher Mathematics, Mumbai is gratefully acknowledged.