Skolem conjectured that the "power sum" A(n) = λ₁α₁ⁿ + ⋯ + λₘαₘⁿ satisfies a certain local-global principle. We prove this conjecture in the case when the multiplicative group generated by α₁,...,αₘ is of rank 1.

Let $k\ge 2$ and define $F^{\left(k\right)}:={\left(F_n^{\left(k\right)}\right)}_{n\ge 0}$, the $k$-generalized Fibonacci sequence whose terms satisfy the recurrence relation $F_n^{\left(k\right)}=F_{n-1}^{\left(k\right)}+F_{n-2}^{\left(k\right)}+\cdots +F_{n-k}^{\left(k\right)}$, with initial conditions $0,0,\cdots ,0,1$ ($k$ terms) and such that the first nonzero term is $F_1^{\left(k\right)}=1$. The sequences $F:=F^{\left(2\right)}$ and $T:=F^{\left(3\right)}$ are the known Fibonacci and Tribonacci sequences, respectively. In 2005, Noe and Post made a conjecture related to the possible solutions of the Diophantine equation $F_n^{\left(k\right)}=F_m^{\left(\ell \right)}$. In this note, we use transcendental tools to provide a general method for finding the intersections $F^{\left(k\right)}\cap F^{\left(m\right)}$ which gives evidence supporting...

For k ≥ 2, the k-generalized Fibonacci sequence $\left(F{ₙ}^{\left(k\right)}\right)ₙ$ is defined to have the initial k terms 0,0,...,0,1 and be such that each term afterwards is the sum of the k preceding terms. We will prove that the number of solutions of the Diophantine equation $F{ₘ}^{\left(k\right)}-F{ₙ}^{\left(\ell \right)}=c>0$ (under some weak assumptions) is bounded by an effectively computable constant depending only on c.

Let $P_m$ and $E_m$ be the $m$-th Padovan and Perrin numbers respectively. Let $r,s$ be non-zero integers with $r\ge 1$ and $s\in \{-1,1\}$, let ${\left\{U_n\right\}}_{n\ge 0}$ be the generalized Lucas sequence given by $U_{n+2}=r{U}_{n+1}+s{U}_n$, with $U_0=0$ and $U_1=1.$ In this paper, we give effective bounds for the solutions of the following Diophantine equations $$P_m=U_n{U}_k\text{and}{E}_m=U_n{U}_k,$$ where $m$, $n$ and $k$ are non-negative integers. Then, we explicitly solve the above Diophantine equations for the Fibonacci, Pell and balancing sequences.

In this paper, we find all Pell and Pell-Lucas numbers written in the form $-2^a-3^b+5^c$, in nonnegative integers $a$, $b$, $c$, with $0\le max\{a,b\}\le c$.

Let ${\left(a_n\right)}_{n\ge 1}$ be the sequence given by $a_1=1$ and $a_n=n^{a_{n-1}}$ for $n\ge 2$. In this paper, we show that the only solution of the equation$$a_1+\cdots +a_n=m^l$$is in positive integers $l\>1,m$ and $n$ is $m=n=1$.

Let $\alpha$ and $\beta$ are conjugate complex algebraic integers which generate Lucas or Lehmer sequences. We present an algorithm to search for elements of such sequences which have no primitive divisors. We use this algorithm to prove that for all $\alpha$ and $\beta$ with h$(\beta /\alpha )\le 4$, the $n$-th element of these sequences has a primitive divisor for $n\>30$. In the course of proving this result, we give an improvement of a result of Stewart concerning more general sequences.

Ce texte montre qu’en combinant le théorème fort des six exponentielles de D.Roy et la conjugaison complexe, on peut obtenir un certain nombre de cas particuliers de la conjecture forte des quatre exponentielles.