Hadamard bent sequences-survey and new results

A new notion of bent sequence related to Hadamard matrices was introduced recently, motivated by a security application (Solé et al, 2021). The subclass of self-dual bent sequences was studied from the standpoint of generation and symmetry (Shi et al., 2022). An analogous study was led for complex Hadamard matrices (Shi et al., submitted). We survey these recent results, and add some new results (asymptotics, Mutually Unbiased Hadamard matrices). MSC (2020): 05B20, 94D10, 94B25