Soient $A,B,C=A+B$ trois éléments de l’ensemble ${\mathbb{N}}^{*}$ des entiers > $0$ (resp. $ℂ\left[X\right]$) des polynômes complexes) premiers entre eux ; on note $r\left(ABC\right)$ le produit des facteurs premiers (resp. le nombre des facteurs premiers dans $ℂ\left[X\right]$) du produit $ABC$. La conjecture $\left(abc\right)$ énonce que, pour tout $ϵ\>0$, il existe $C_{ϵ}\>0$ pour lequel l’inégalité : $r\left(ABC\right)\ge C_{ϵ}{S}^{1-ϵ}$ avec $S=$ max$(A,B,C)$) est toujours vérifiée. Le théorème de Mason établit l’inégalité, $D$ (supposé > $0$) désignant le plus grand des degrés des polynômes $A,B,C:r\left(ABC\right)\ge D+1$. Les cas de triplets de polynômes où l’égalité...

In this note, particular inequalities of DVT-type in real and integer numbers are investigated.

Given a binary recurrence ${u_n}_{n\ge 0}$, we consider the Diophantine equation $u_{n_1}^{x_1}\cdots u_{n_L}^{x_L}=1$ with nonnegative integer unknowns $n_1,...,n_L$, where $n_i\ne n_j$ for 1 ≤ i < j ≤ L, $max|x_i|:1\le i\le L\le K$, and K is a fixed parameter. We show that the above equation has only finitely many solutions and the largest one can be explicitly bounded. We demonstrate the strength of our method by completely solving a particular Diophantine equation of the above form.

Let F(X,Y) be an irreducible binary cubic form with integer coefficients and positive discriminant D. Let k be a positive integer satisfying $k<\left({\left(3D\right)}^{1/4}\right)/2\pi$. We give improved upper bounds for the number of primitive solutions of the Thue inequality $\left|F\right(X,Y\left)\right|\le k$.

We study numerical semigroups $S$ with the property that if $m$ is the multiplicity of $S$ and $w\left(i\right)$ is the least element of $S$ congruent with $i$ modulo $m$, then $0<w\left(1\right)<\cdots <w(m-1)$. 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.