Sur les fagots, les contrefagots, les déter-cubes et leurs applications
On décrit l’algèbre des invariants de l’action naturelle du groupe sur les pinceaux de formes quintiques binaires.
The inertia of an by symmetric sign pattern is called maximal when it is not a proper subset of the inertia of another symmetric sign pattern of order . In this note we classify all the maximal inertias for symmetric sign patterns of order , and identify symmetric sign patterns with maximal inertias by using a rank-one perturbation.
We discuss the existence of an orthogonal basis consisting of decomposable vectors for all symmetry classes of tensors associated with semi-dihedral groups . In particular, a necessary and sufficient condition for the existence of such a basis associated with and degree two characters is given.