New classes of p-ary bent functions

The article of record as published may be found at https://doi.org/10.1007/s12095-018-0290-9In this paper, we consider the p-ary functions from Fnp to Fp, where p is an odd prime. We characterize the subspace sum concept (depending upon the derivative) and give many of its properties. In particular, we show that the subspace sum of p-ary functions with respect to a subspace of Fnp is an affine invariant. Further, we construct two new classes of p-ary bent functions, which do not contain one another.The first two authors thank the Centre of Excellence in Cryptology (CoEC) and R. C. Bose Centre for Cryptology and Security of Indian Statistical Institute, Kolkata, for supporting their visits at the Indian Statistical Institute, Kolkata, during which period the above work was carried on