2021/09/28 by Tang, Chunming, Han, Peng, Wang, Qi +2
#FOS: Computer and information sciences #Information Theory (cs.IT)
paper · doi:10.48550/arxiv.2109.13421
Let n=2m. In the present paper, we study the binomial Boolean functions of the form fa,b(x) = Tr1n(a x2m-1 ) +Tr12(bx(2n-1)/(3) ), where m is an even positive integer, a∈ \mathbbF2n^* and b∈ \mathbbF4^*. We show that fa,b is a bent function if the Kloosterman sum Km(a2m+1)=1+ ∑_x∈ \mathbbF2m^* (-1)^Tr1m(a2m+1 x+ (1)/(x)) equals 4, thus settling an open problem of Mesnager. The proof employs tools including computing Walsh coefficients of Boolean functions via multiplicative characters, divisibility properties of Gauss sums, and graph theory.