2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/62979We first include a result of the second author showing that the Banach space S is complementably minimal. We then show that every block sequence of the unit vector basis of S has a subsequence which spans a space isomorphic to its square. By the Pełczyński decomposition method it follows that every basic sequence in S which spans a space complemented in S has a subsequence which spans a space isomorphic to S (i.e. S is a subsequentially prime space).See also: http://www.math.sc.edu/~giorgis/research.htmlFunctional Analysis46B03, 46B20text