On a class of permutation trinomials over finite fields

Abstract

In this paper, we study the permutation properties of the class of trinomials of the form f (x ) = x( 4q+1 )+ lambda (1 )x (q +4) + lambda( 2 )x (2q +3) is an element of F (q) 2 [x ] , where lambda( 1 ), lambda (2) is an element of F (q) and they are not simultaneously zero. We find all necessary and sufficient conditions on lambda (1) and lambda (2) such that f (x ) permutes F( q )2 , where q is odd and q = 2( 2k+1) , k is an element of N.