Notes on TQFT wire models and coherence equations for triangular cells.
Notion de demi-bande : demi-bande de type deux.
Notiz über die Discontinuität gewisser Collineationsgruppen
Null cones and pseudo-riemannian metrics.
Number of algebraic operations in idempotent groupoids
Number of indecomposable summands in direct decompositions of torsion-free abelian groups
Number of solutions in a box of a linear equation in an Abelian group
For every finite Abelian group Γ and for all , if there exists a solution of the equation in non-negative integers , where are positive integers, then the number of such solutions is estimated from below in the best possible way.
Number of solutions in a box of a linear homogeneous equation in an Abelian group
Numerical invariants of exponential groups and locally free approximation of the braid group.
Numerical isotonies of preordered semigroups through the concept of a scale.
Numerical semigroups of maximal and almost maximal length.
Numerical semigroups with a monotonic Apéry set
We study numerical semigroups with the property that if is the multiplicity of and is the least element of congruent with modulo , then . The set of numerical semigroups with this property and fixed multiplicity is bijective with an affine semigroup and consequently it can be described by a finite set of parameters. Invariants like the gender, type, embedding dimension and Frobenius number are computed for several families of this kind of numerical semigroups.
n-арные инверсные квазигруппы (J-квазигруппы)