Self-dual bent sequences for complex Hadamard matrices

A new notion of bent sequence related to Hadamard matrices was introduced recently, motivated by a security application (Solé et al. 2021). In this paper we introduce the analogous for complex matrices, and study self-dual class in length at most 90. We use three competing methods generation: Brute force, Linear Algebra Groebner bases. Regular Bush-type provide many examples. strong automorphism group which acts on their associated sequences. give an efficient algorithm compute that group. also answer question can be uniquely reconstructed from off-diagonal elements, define concept mixed-skew matrix, show existence small orders.