On APN functions L_1(x~3)+L_2(x~9) with linear L_1 and L_2

摘要

In a recent paper by L. Budaghyan, C. Carlet, and G. Leander (2009) it is shown that functions of the form L-1(x(3)) + L-2(x(9)), where L-1 and L-2 are linear, are a good source for construction of new infinite families of APN functions. In the present work we study necessary and sufficient conditions for such functions to be APN.