You are cordially invited to attend

**two**colloquia this week given by Nurdagül Anbar (RICAM, Austria) on**Wednesday, 6 December 2017, in FENS-G055 at 11 am**, and by John Sheekey (UCD, Ireland) on**Thursday, 7 December 2017, in FENS-L063****at 11 am.**Title: Modified planar functions, bent4 functions and their relative difference sets

**S**

**peaker:**

**Nurdagül Anbar**

**Date/Time:**Wednesday, 6 December 2017, at 11 am

**Place:**in FENS-G055

**Abstract:**Modified planar functions are introduced to describe (2n,2n,2n,1) relative difference sets (RDS) R as a graph of a function on the finite field F2n. These are analogs of planar functions in odd characteristic q to describe (qn, qn, qn, 1) RDSs. We point out that the projections of R are (2n, 2, 2n, 2n−1) RDS that can be described by bent4 functions, and we investigate the equivalence of their relative difference sets. In particular, we show that two extended affine equivalent bent functions may give rise to bent4 functions whose corresponding RDSs are inequivalent.