Abstract
Let S be a semigroup and \(z_{0}\) a fixed element in S. We determine the complex-valued solutions of the following Kannappan-sine addition law \(f(xyz_{0})=f(x)g(y)+f(y)g(x),x,y\in S.\)
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Ahmed, J., Omar, A. & Elhoucien, E. A Kannappan-sine addition law on semigroups. Aequat. Math. (2024). https://doi.org/10.1007/s00010-024-01104-x
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DOI: https://doi.org/10.1007/s00010-024-01104-x