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In this paper, we consider almost S-manifolds. We study symmetries of these type manifolds, especially weak symmetries and Ricci symmetries. We get some conditions for non-existence weakly symmetric and weakly Ricci symmetric almost S-manifolds and we obtain a phi-symmetric and phi-Ricci symmetric almost S-manifolds is an etha-Einstein manifold under some conditions.

S-structures, almost S-manifolds, weakly symmetric manifolds, phi-Ricci symmetric manifolds