2021-06-282021-06-282020Armario Sampalo, J.A. y Flannery, D.L. (2020). Almost supplementary difference sets and quaternary sequences with optimal autocorrelation. Cryptography and Communications, 12 (4), 757-768.1936-2447https://hdl.handle.net/11441/114896We introduce almost supplementary difference sets (ASDS). For odd m, certain ASDS in Zm that have amicable incidence matrices are equivalent to quaternary sequences of odd length m with optimal autocorrelation. As one consequence, if 2m − 1 is a prime power, or m 1 mod 4 is prime, then ASDS of this kind exist. We also explore connections to optimal binary sequences and group cohomology.application/pdf13engAttribution-NonCommercial-NoDerivatives 4.0 Internacionalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccess10.1007/s12095-019-00418-x