Symmetrization and sharp Sobolev inequalities in metric spaces
Symmetry group analysis of weak solutions
Syndetic Sets and Amenability
Systems formed by translates of one element in $L_p(\mathbb R)$
Szego limit theorem for operators with discontinuous symbols and applications to entanglement entropy
Szegö limit theorems for operators with almost periodic diagonals
Szemeredi's theorem, frequent hypercyclicity and multiple recurrence
Szlenk indices and uniform homeomorphisms