MATHEMATICA BOHEMICA, Vol. 137, No. 4, pp. 403-413, 2012

On the intersection of two distinct $k$-generalized Fibonacci sequences

Diego Marques

Diego Marques, University of Brasilia, CEP: 70910-900, Brasilia, Brazil, e-mail: diego@mat.unb.br

Abstract: Let $k\geq2$ and define $F^{(k)}:=(F_n^{(k)})_{n\geq0}$, the $k$-generalized Fibonacci sequence whose terms satisfy the recurrence relation $F_n^{(k)}=F_{n-1}^{(k)}+F_{n-2}^{(k)}+\cdots+ F_{n-k}^{(k)}$, with initial conditions $0,0,\dots,0,1$ ($k$ terms) and such that the first nonzero term is $F_1^{(k)}=1$. The sequences $F:=F^{(2)}$ and $T:=F^{(3)}$ 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 $F_n^{(k)}=F_m^{(\ell)}$. In this note, we use transcendental tools to provide a general method for finding the intersections $F^{(k)}\cap F^{(m)}$ which gives evidence supporting the Noe-Post conjecture. In particular, we prove that $F\cap T=\{0,1,2,13\}$.

Keywords: $k$-generalized Fibonacci numbers, linear forms in logarithms, reduction method

Classification (MSC 2010): 11B39, 11D61, 11J86


Full text available as PDF.

Access to the full text of journal articles on this site is restricted to the subscribers of Myris Trade. To activate your access, please contact Myris Trade at myris@myris.cz.


[Previous Article] [Next Article] [Contents of This Number] [Contents of Mathematica Bohemica]
[Full text of the older issues of Mathematica Bohemica at DML-CZ]